diff --git a/dev/benchmarks/complex_layout/test_memory/scroll_perf.dart b/dev/benchmarks/complex_layout/test_memory/scroll_perf.dart
deleted file mode 100644
index c42f8b005b5..00000000000
--- a/dev/benchmarks/complex_layout/test_memory/scroll_perf.dart
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'dart:async';
-
-import 'package:complex_layout/main.dart';
-import 'package:flutter/material.dart';
-import 'package:flutter/scheduler.dart';
-import 'package:flutter_test/flutter_test.dart';
-
-/// The speed, in pixels per second, that the drag gestures should end with.
-const double speed = 1500.0;
-
-/// The number of down drags and the number of up drags. The total number of
-/// gestures is twice this number.
-const int maxIterations = 4;
-
-/// The time that is allowed between gestures for the fling effect to settle.
-const Duration pauses = Duration(milliseconds: 500);
-
-Future<void> main() async {
-  final Completer<void> ready = new Completer<void>();
-  runApp(new GestureDetector(
-    onTap: () {
-      debugPrint('Received tap.');
-      ready.complete();
-    },
-    behavior: HitTestBehavior.opaque,
-    child: new IgnorePointer(
-      ignoring: true,
-      child: new ComplexLayoutApp(),
-    ),
-  ));
-  await SchedulerBinding.instance.endOfFrame;
-
-  /// Wait 50ms to allow the GPU thread to actually put up the frame. (The
-  /// endOfFrame future ends when we send the data to the engine, before the GPU
-  /// thread has had a chance to rasterize, etc.)
-  await new Future<Null>.delayed(const Duration(milliseconds: 50));
-  debugPrint('==== MEMORY BENCHMARK ==== READY ====');
-
-  await ready.future; // waits for tap sent by devicelab task
-  debugPrint('Continuing...');
-
-  // remove onTap handler, enable pointer events for app
-  runApp(new GestureDetector(
-    child: new IgnorePointer(
-      ignoring: false,
-      child: new ComplexLayoutApp(),
-    ),
-  ));
-  await SchedulerBinding.instance.endOfFrame;
-
-  final WidgetController controller = new LiveWidgetController(WidgetsBinding.instance);
-
-  // Scroll down
-  for (int iteration = 0; iteration < maxIterations; iteration += 1) {
-    debugPrint('Scroll down... $iteration/$maxIterations');
-    await controller.fling(find.byType(ListView), const Offset(0.0, -700.0), speed);
-    await new Future<Null>.delayed(pauses);
-  }
-
-  // Scroll up
-  for (int iteration = 0; iteration < maxIterations; iteration += 1) {
-    debugPrint('Scroll up... $iteration/$maxIterations');
-    await controller.fling(find.byType(ListView), const Offset(0.0, 300.0), speed);
-    await new Future<Null>.delayed(pauses);
-  }
-
-  debugPrint('==== MEMORY BENCHMARK ==== DONE ====');
-}
diff --git a/dev/devicelab/bin/tasks/complex_layout_scroll_perf__memory.dart b/dev/devicelab/bin/tasks/complex_layout_scroll_perf__memory.dart
index 1729629efd8..ff68529f472 100644
--- a/dev/devicelab/bin/tasks/complex_layout_scroll_perf__memory.dart
+++ b/dev/devicelab/bin/tasks/complex_layout_scroll_perf__memory.dart
@@ -4,16 +4,11 @@
 
 import 'dart:async';
 
+import 'package:flutter_devicelab/tasks/perf_tests.dart';
 import 'package:flutter_devicelab/framework/adb.dart';
 import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/framework/utils.dart';
-import 'package:flutter_devicelab/tasks/perf_tests.dart';
 
 Future<Null> main() async {
   deviceOperatingSystem = DeviceOperatingSystem.android;
-  await task(new MemoryTest(
-    '${flutterDirectory.path}/dev/benchmarks/complex_layout',
-    'test_memory/scroll_perf.dart',
-    'com.yourcompany.complexLayout',
-  ).run);
+  await task(createComplexLayoutScrollMemoryTest());
 }
diff --git a/dev/devicelab/bin/tasks/flutter_gallery__back_button_memory.dart b/dev/devicelab/bin/tasks/flutter_gallery__back_button_memory.dart
index f66573015a8..a7880307a8f 100644
--- a/dev/devicelab/bin/tasks/flutter_gallery__back_button_memory.dart
+++ b/dev/devicelab/bin/tasks/flutter_gallery__back_button_memory.dart
@@ -2,57 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-/// Measure application memory usage after pausing and resuming the app
-/// with the Android back button.
-
 import 'dart:async';
 
-import 'package:flutter_devicelab/framework/adb.dart';
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/framework/utils.dart';
 import 'package:flutter_devicelab/tasks/perf_tests.dart';
-
-const String packageName = 'io.flutter.demo.gallery';
-const String activityName = 'io.flutter.demo.gallery.MainActivity';
-
-class BackButtonMemoryTest extends MemoryTest {
-  BackButtonMemoryTest() : super('${flutterDirectory.path}/examples/flutter_gallery', 'test_memory/back_button.dart', packageName);
-
-  @override
-  AndroidDevice get device => super.device;
-
-  /// Perform a series of back button suspend and resume cycles.
-  @override
-  Future<void> useMemory() async {
-    await launchApp();
-    await recordStart();
-    for (int iteration = 0; iteration < 10; iteration += 1) {
-      print('back/forward iteration $iteration');
-
-      // Push back button, wait for it to be seen by the Flutter app.
-      prepareForNextMessage('AppLifecycleState.paused');
-      await device.shellExec('input', <String>['keyevent', 'KEYCODE_BACK']);
-      await receivedNextMessage;
-
-      // Give Android time to settle (e.g. run GCs) after closing the app.
-      await new Future<Null>.delayed(const Duration(milliseconds: 100));
-
-      // Relaunch the app, wait for it to launch.
-      prepareForNextMessage('READY');
-      final String output = await device.shellEval('am', <String>['start', '-n', '$packageName/$activityName']);
-      print('adb shell am start: $output');
-      if (output.contains('Error'))
-        fail('unable to launch activity');
-      await receivedNextMessage;
-
-      // Wait for the Flutter app to settle (e.g. run GCs).
-      await new Future<Null>.delayed(const Duration(milliseconds: 100));
-    }
-    await recordEnd();
-  }
-}
+import 'package:flutter_devicelab/framework/framework.dart';
 
 Future<Null> main() async {
-  deviceOperatingSystem = DeviceOperatingSystem.android;
-  await task(new BackButtonMemoryTest().run);
+  await task(createGalleryBackButtonMemoryTest());
 }
diff --git a/dev/devicelab/bin/tasks/flutter_gallery__memory_nav.dart b/dev/devicelab/bin/tasks/flutter_gallery__memory_nav.dart
index 8c2b301e97e..90217afb344 100644
--- a/dev/devicelab/bin/tasks/flutter_gallery__memory_nav.dart
+++ b/dev/devicelab/bin/tasks/flutter_gallery__memory_nav.dart
@@ -4,14 +4,9 @@
 
 import 'dart:async';
 
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/framework/utils.dart';
 import 'package:flutter_devicelab/tasks/perf_tests.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
 
 Future<Null> main() async {
-  await task(new MemoryTest(
-    '${flutterDirectory.path}/examples/flutter_gallery',
-    'test_memory/memory_nav.dart',
-    'io.flutter.demo.gallery',
-  ).run);
+  await task(createGalleryNavigationMemoryTest());
 }
diff --git a/dev/devicelab/bin/tasks/hello_world__memory.dart b/dev/devicelab/bin/tasks/hello_world__memory.dart
index f3a99aebc61..16898ac77c7 100644
--- a/dev/devicelab/bin/tasks/hello_world__memory.dart
+++ b/dev/devicelab/bin/tasks/hello_world__memory.dart
@@ -4,36 +4,9 @@
 
 import 'dart:async';
 
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/framework/utils.dart';
 import 'package:flutter_devicelab/tasks/perf_tests.dart';
-
-class HelloWorldMemoryTest extends MemoryTest {
-  HelloWorldMemoryTest() : super(
-    '${flutterDirectory.path}/examples/hello_world',
-    'lib/main.dart',
-    'io.flutter.examples.hello_world',
-  );
-
-  /// Launch an app with no instrumentation and measure its memory usage after
-  /// 1.5s and 3.0s.
-  @override
-  Future<void> useMemory() async {
-    print('launching $project$test on device...');
-    await flutter('run', options: <String>[
-      '--verbose',
-      '--release',
-      '--no-resident',
-      '-d', device.deviceId,
-      test,
-    ]);
-    await new Future<Null>.delayed(const Duration(milliseconds: 1500));
-    await recordStart();
-    await new Future<Null>.delayed(const Duration(milliseconds: 3000));
-    await recordEnd();
-  }
-}
+import 'package:flutter_devicelab/framework/framework.dart';
 
 Future<Null> main() async {
-  await task(new HelloWorldMemoryTest().run);
+  await task(createHelloWorldMemoryTest());
 }
diff --git a/dev/devicelab/lib/framework/adb.dart b/dev/devicelab/lib/framework/adb.dart
index 6849e03dd62..de65020a0fd 100644
--- a/dev/devicelab/lib/framework/adb.dart
+++ b/dev/devicelab/lib/framework/adb.dart
@@ -83,18 +83,9 @@ abstract class Device {
   /// Assumes the device doesn't have a secure unlock pattern.
   Future<Null> unlock();
 
-  /// Emulate a tap on the touch screen.
-  Future<Null> tap(int x, int y);
-
   /// Read memory statistics for a process.
   Future<Map<String, dynamic>> getMemoryStats(String packageName);
 
-  /// Stream the system log from the device.
-  ///
-  /// Flutter applications' `print` statements end up in this log
-  /// with some prefix.
-  Stream<String> get logcat;
-
   /// Stop a process.
   Future<Null> stop(String packageName);
 }
@@ -246,11 +237,6 @@ class AndroidDevice implements Device {
     await shellExec('input', const <String>['keyevent', '82']);
   }
 
-  @override
-  Future<Null> tap(int x, int y) async {
-    await shellExec('input', <String>['tap', '$x', '$y']);
-  }
-
   /// Retrieves device's wakefulness state.
   ///
   /// See: https://android.googlesource.com/platform/frameworks/base/+/master/core/java/android/os/PowerManagerInternal.java
@@ -285,63 +271,6 @@ class AndroidDevice implements Device {
     };
   }
 
-  @override
-  Stream<String> get logcat {
-    final Completer<void> stdoutDone = new Completer<void>();
-    final Completer<void> stderrDone = new Completer<void>();
-    final Completer<void> processDone = new Completer<void>();
-    final Completer<void> abort = new Completer<void>();
-    bool aborted = false;
-    StreamController<String> stream;
-    stream = new StreamController<String>(
-      onListen: () async {
-        await adb(<String>['logcat', '--clear']);
-        final Process process = await startProcess(adbPath, <String>['-s', deviceId, 'logcat']);
-        process.stdout
-          .transform(utf8.decoder)
-          .transform(const LineSplitter())
-          .listen((String line) {
-            print('adb logcat: $line');
-            stream.sink.add(line);
-          }, onDone: () { stdoutDone.complete(); });
-        process.stderr
-          .transform(utf8.decoder)
-          .transform(const LineSplitter())
-          .listen((String line) {
-            print('adb logcat stderr: $line');
-          }, onDone: () { stderrDone.complete(); });
-        process.exitCode.then((int exitCode) {
-          print('adb logcat process terminated with exit code $exitCode');
-          if (!aborted) {
-            stream.addError(BuildFailedError('adb logcat failed with exit code $exitCode.'));
-            processDone.complete();
-          }
-        });
-        await Future.any<dynamic>(<Future<dynamic>>[
-          Future.wait<void>(<Future<void>>[
-            stdoutDone.future,
-            stderrDone.future,
-            processDone.future,
-          ]),
-          abort.future,
-        ]);
-        aborted = true;
-        print('terminating adb logcat');
-        process.kill();
-        print('closing logcat stream');
-        await stream.close();
-      },
-      onCancel: () {
-        if (!aborted) {
-          print('adb logcat aborted');
-          aborted = true;
-          abort.complete();
-        }
-      },
-    );
-    return stream.stream;
-  }
-
   @override
   Future<Null> stop(String packageName) async {
     return shellExec('am', <String>['force-stop', packageName]);
@@ -442,21 +371,11 @@ class IosDevice implements Device {
   @override
   Future<Null> unlock() async {}
 
-  @override
-  Future<Null> tap(int x, int y) async {
-    throw 'Not implemented';
-  }
-
   @override
   Future<Map<String, dynamic>> getMemoryStats(String packageName) async {
     throw 'Not implemented';
   }
 
-  @override
-  Stream<String> get logcat {
-    throw 'Not implemented';
-  }
-
   @override
   Future<Null> stop(String packageName) async {}
 }
diff --git a/dev/devicelab/lib/framework/framework.dart b/dev/devicelab/lib/framework/framework.dart
index 3ad25f5118b..aa6c3a81410 100644
--- a/dev/devicelab/lib/framework/framework.dart
+++ b/dev/devicelab/lib/framework/framework.dart
@@ -81,15 +81,12 @@ class _TaskRunner {
   Future<TaskResult> run(Duration taskTimeout) async {
     try {
       _taskStarted = true;
-      print('Running task.');
       final TaskResult result = await _performTask().timeout(taskTimeout);
       _completer.complete(result);
       return result;
     } on TimeoutException catch (_) {
-      print('Task timed out after $taskTimeout.');
       return new TaskResult.failure('Task timed out after $taskTimeout');
     } finally {
-      print('Cleaning up after task...');
       await forceQuitRunningProcesses();
       _closeKeepAlivePort();
     }
diff --git a/dev/devicelab/lib/framework/utils.dart b/dev/devicelab/lib/framework/utils.dart
index 3263000b70d..fc3a7779b11 100644
--- a/dev/devicelab/lib/framework/utils.dart
+++ b/dev/devicelab/lib/framework/utils.dart
@@ -244,7 +244,7 @@ Future<Null> forceQuitRunningProcesses() async {
 
   // Whatever's left, kill it.
   for (ProcessInfo p in _runningProcesses) {
-    print('Force-quitting process:\n$p');
+    print('Force quitting process:\n$p');
     if (!p.process.kill()) {
       print('Failed to force quit process');
     }
@@ -528,6 +528,8 @@ int parseServicePort(String line, {
   // e.g. "An Observatory debugger and profiler on ... is available at: http://127.0.0.1:8100/"
   final RegExp pattern = new RegExp('$prefix(\\S+:(\\d+)/\\S*)\$', multiLine: multiLine);
   final Match match = pattern.firstMatch(line);
+  print(pattern);
+  print(match);
   return match == null ? null : int.parse(match.group(2));
 }
 
diff --git a/dev/devicelab/lib/tasks/perf_tests.dart b/dev/devicelab/lib/tasks/perf_tests.dart
index 0d31ef63ff3..15fca3a0588 100644
--- a/dev/devicelab/lib/tasks/perf_tests.dart
+++ b/dev/devicelab/lib/tasks/perf_tests.dart
@@ -7,7 +7,7 @@ import 'dart:convert' show json;
 import 'dart:io';
 
 import 'package:meta/meta.dart';
-import 'package:path/path.dart' as path;
+import 'package:path/path.dart' as p;
 
 import '../framework/adb.dart';
 import '../framework/framework.dart';
@@ -30,6 +30,14 @@ TaskFunction createTilesScrollPerfTest() {
   ).run;
 }
 
+TaskFunction createComplexLayoutScrollMemoryTest() {
+  return new MemoryTest(
+    '${flutterDirectory.path}/dev/benchmarks/complex_layout',
+    'com.yourcompany.complexLayout',
+    testTarget: 'test_driver/scroll_perf.dart',
+  ).run;
+}
+
 TaskFunction createFlutterGalleryStartupTest() {
   return new StartupTest(
     '${flutterDirectory.path}/examples/flutter_gallery',
@@ -54,6 +62,29 @@ TaskFunction createComplexLayoutCompileTest() {
   return new CompileTest('${flutterDirectory.path}/dev/benchmarks/complex_layout').run;
 }
 
+TaskFunction createHelloWorldMemoryTest() {
+  return new MemoryTest(
+    '${flutterDirectory.path}/examples/hello_world',
+    'io.flutter.examples.hello_world',
+  ).run;
+}
+
+TaskFunction createGalleryNavigationMemoryTest() {
+  return new MemoryTest(
+    '${flutterDirectory.path}/examples/flutter_gallery',
+    'io.flutter.demo.gallery',
+    testTarget: 'test_driver/memory_nav.dart',
+  ).run;
+}
+
+TaskFunction createGalleryBackButtonMemoryTest() {
+  return new AndroidBackButtonMemoryTest(
+    '${flutterDirectory.path}/examples/flutter_gallery',
+    'io.flutter.demo.gallery',
+    'io.flutter.demo.gallery.MainActivity',
+  ).run;
+}
+
 TaskFunction createFlutterViewStartupTest() {
   return new StartupTest(
       '${flutterDirectory.path}/examples/flutter_view',
@@ -335,15 +366,15 @@ class CompileTest {
 
   static Future<Map<String, dynamic>> getSizesFromIosApp(String appPath) async {
     // Thin the binary to only contain one architecture.
-    final String xcodeBackend = path.join(flutterDirectory.path, 'packages', 'flutter_tools', 'bin', 'xcode_backend.sh');
+    final String xcodeBackend = p.join(flutterDirectory.path, 'packages', 'flutter_tools', 'bin', 'xcode_backend.sh');
     await exec(xcodeBackend, <String>['thin'], environment: <String, String>{
       'ARCHS': 'arm64',
-      'WRAPPER_NAME': path.basename(appPath),
-      'TARGET_BUILD_DIR': path.dirname(appPath),
+      'WRAPPER_NAME': p.basename(appPath),
+      'TARGET_BUILD_DIR': p.dirname(appPath),
     });
 
-    final File appFramework = new File(path.join(appPath, 'Frameworks', 'App.framework', 'App'));
-    final File flutterFramework = new File(path.join(appPath, 'Frameworks', 'Flutter.framework', 'Flutter'));
+    final File appFramework = new File(p.join(appPath, 'Frameworks', 'App.framework', 'App'));
+    final File flutterFramework = new File(p.join(appPath, 'Frameworks', 'Flutter.framework', 'Flutter'));
 
     return <String, dynamic>{
       'app_framework_uncompressed_bytes': await appFramework.length(),
@@ -389,167 +420,123 @@ class CompileTest {
 
 /// Measure application memory usage.
 class MemoryTest {
-  MemoryTest(this.project, this.test, this.package);
+  const MemoryTest(this.testDirectory, this.packageName, { this.testTarget });
 
-  final String project;
-  final String test;
-  final String package;
+  final String testDirectory;
+  final String packageName;
 
-  /// Completes when the log line specified in the last call to
-  /// [prepareForNextMessage] is seen by `adb logcat`.
-  Future<void> get receivedNextMessage => _receivedNextMessage?.future;
-  Completer<void> _receivedNextMessage;
-  String _nextMessage;
-
-  /// Prepares the [receivedNextMessage] future such that it will complete
-  /// when `adb logcat` sees a log line with the given `message`.
-  void prepareForNextMessage(String message) {
-    _nextMessage = message;
-    _receivedNextMessage = new Completer<void>();
-  }
-
-  int get iterationCount => 15;
-
-  Device get device => _device;
-  Device _device;
+  /// Path to a flutter driver script that will run after starting the app.
+  ///
+  /// If not specified, then the test will start the app, gather statistics, and then exit.
+  final String testTarget;
 
   Future<TaskResult> run() {
-    return inDirectory(project, () async {
-      // This test currently only works on Android, because device.logcat,
-      // device.getMemoryStats, etc, aren't implemented for iOS.
-
-      _device = await devices.workingDevice;
+    return inDirectory(testDirectory, () async {
+      final Device device = await devices.workingDevice;
       await device.unlock();
+      final String deviceId = device.deviceId;
       await flutter('packages', options: <String>['get']);
 
       if (deviceOperatingSystem == DeviceOperatingSystem.ios)
-        await prepareProvisioningCertificates(project);
+        await prepareProvisioningCertificates(testDirectory);
 
-      final StreamSubscription<String> adb = device.logcat.listen(
-        (String data) {
-          if (data.contains('==== MEMORY BENCHMARK ==== $_nextMessage ===='))
-            _receivedNextMessage.complete();
-        },
-      );
+      final List<String> runOptions = <String>[
+        '-v',
+        '--profile',
+        '--trace-startup', // wait for the first frame to render
+        '-d',
+        deviceId,
+        '--observatory-port',
+        '0',
+      ];
+      if (testTarget != null)
+        runOptions.addAll(<String>['-t', testTarget]);
+      final String output = await evalFlutter('run', options: runOptions);
+      final int observatoryPort = parseServicePort(output, prefix: 'Successfully connected to service protocol: ', multiLine: true);
+      if (observatoryPort == null)
+        throw new Exception('Could not find observatory port in "flutter run" output.');
 
-      for (int iteration = 0; iteration < iterationCount; iteration += 1) {
-        print('running memory test iteration $iteration...');
-        _startMemoryUsage = null;
-        await useMemory();
-        assert(_startMemoryUsage != null);
-        assert(_startMemory.length == iteration + 1);
-        assert(_endMemory.length == iteration + 1);
-        assert(_diffMemory.length == iteration + 1);
-        print('terminating...');
-        await device.stop(package);
-        await new Future<void>.delayed(const Duration(milliseconds: 10));
+      final Map<String, dynamic> startData = await device.getMemoryStats(packageName);
+
+      final Map<String, dynamic> data = <String, dynamic>{
+         'start_total_kb': startData['total_kb'],
+      };
+
+      if (testTarget != null) {
+        await flutter('drive', options: <String>[
+          '-v',
+          '-t',
+          testTarget,
+          '-d',
+          deviceId,
+          '--use-existing-app=http://localhost:$observatoryPort',
+        ]);
+
+        final Map<String, dynamic> endData = await device.getMemoryStats(packageName);
+        data['end_total_kb'] = endData['total_kb'];
+        data['diff_total_kb'] = endData['total_kb'] - startData['total_kb'];
       }
 
-      await adb.cancel();
+      await device.stop(packageName);
 
-      final ListStatistics startMemoryStatistics = new ListStatistics(_startMemory);
-      final ListStatistics endMemoryStatistics = new ListStatistics(_endMemory);
-      final ListStatistics diffMemoryStatistics = new ListStatistics(_diffMemory);
-
-      final Map<String, dynamic> memoryUsage = <String, dynamic>{};
-      memoryUsage.addAll(startMemoryStatistics.asMap('start'));
-      memoryUsage.addAll(endMemoryStatistics.asMap('end'));
-      memoryUsage.addAll(diffMemoryStatistics.asMap('diff'));
-
-      _device = null;
-      _startMemory.clear();
-      _endMemory.clear();
-      _diffMemory.clear();
-
-      return new TaskResult.success(memoryUsage, benchmarkScoreKeys: memoryUsage.keys.toList());
+      return new TaskResult.success(data, benchmarkScoreKeys: data.keys.toList());
     });
   }
-
-  /// Starts the app specified by [test] on the [device].
-  ///
-  /// The [run] method will terminate it by its package name ([package]).
-  Future<void> launchApp() async {
-    prepareForNextMessage('READY');
-    print('launching $project$test on device...');
-    await flutter('run', options: <String>[
-      '--verbose',
-      '--release',
-      '--no-resident',
-      '-d', device.deviceId,
-      test,
-    ]);
-    print('awaiting "ready" message...');
-    await receivedNextMessage;
-  }
-
-  /// To change the behaviour of the test, override this.
-  ///
-  /// Make sure to call recordStart() and recordEnd() once each in that order.
-  ///
-  /// By default it just launches the app, records memory usage, taps the device,
-  /// awaits a DONE notification, and records memory usage again.
-  Future<void> useMemory() async {
-    await launchApp();
-    await recordStart();
-
-    prepareForNextMessage('DONE');
-    print('tapping device...');
-    await device.tap(100, 100);
-    print('awaiting "done" message...');
-    await receivedNextMessage;
-
-    await recordEnd();
-  }
-
-  final List<int> _startMemory = <int>[];
-  final List<int> _endMemory = <int>[];
-  final List<int> _diffMemory = <int>[];
-
-  Map<String, dynamic> _startMemoryUsage;
-
-  @protected
-  Future<void> recordStart() async {
-    assert(_startMemoryUsage == null);
-    print('snapshotting memory usage...');
-    _startMemoryUsage = await device.getMemoryStats(package);
-  }
-
-  @protected
-  Future<void> recordEnd() async {
-    assert(_startMemoryUsage != null);
-    print('snapshotting memory usage...');
-    final Map<String, dynamic> endMemoryUsage = await device.getMemoryStats(package);
-    _startMemory.add(_startMemoryUsage['total_kb']);
-    _endMemory.add(endMemoryUsage['total_kb']);
-    _diffMemory.add(endMemoryUsage['total_kb'] - _startMemoryUsage['total_kb']);
-  }
 }
 
-/// Holds simple statistics of an odd-lengthed list of integers.
-class ListStatistics {
-  factory ListStatistics(Iterable<int> data) {
-    assert(data.isNotEmpty);
-    assert(data.length % 2 == 1);
-    final List<int> sortedData = data.toList()..sort();
-    return new ListStatistics._(
-      sortedData.first,
-      sortedData.last,
-      sortedData[(sortedData.length - 1) ~/ 2],
-    );
-  }
+/// Measure application memory usage after pausing and resuming the app
+/// with the Android back button.
+class AndroidBackButtonMemoryTest {
+  const AndroidBackButtonMemoryTest(this.testDirectory, this.packageName, this.activityName);
 
-  const ListStatistics._(this.min, this.max, this.median);
+  final String testDirectory;
+  final String packageName;
+  final String activityName;
 
-  final int min;
-  final int max;
-  final int median;
+  Future<TaskResult> run() {
+    return inDirectory(testDirectory, () async {
+      if (deviceOperatingSystem != DeviceOperatingSystem.android) {
+        throw 'This test is only supported on Android';
+      }
 
-  Map<String, int> asMap(String prefix) {
-    return <String, int>{
-      '$prefix-min': min,
-      '$prefix-max': max,
-      '$prefix-median': median,
-    };
+      final AndroidDevice device = await devices.workingDevice;
+      await device.unlock();
+      final String deviceId = device.deviceId;
+      await flutter('packages', options: <String>['get']);
+
+      await flutter('run', options: <String>[
+        '-v',
+        '--profile',
+        '--trace-startup', // wait for the first frame to render
+        '-d',
+        deviceId,
+      ]);
+
+      final Map<String, dynamic> startData = await device.getMemoryStats(packageName);
+
+      final Map<String, dynamic> data = <String, dynamic>{
+         'start_total_kb': startData['total_kb'],
+      };
+
+      // Perform a series of back button suspend and resume cycles.
+      for (int i = 0; i < 10; i++) {
+        await device.shellExec('input', <String>['keyevent', 'KEYCODE_BACK']);
+        await new Future<Null>.delayed(const Duration(milliseconds: 1000));
+        final String output = await device.shellEval('am', <String>['start', '-n', '$packageName/$activityName']);
+        print(output);
+        if (output.contains('Error'))
+          return new TaskResult.failure('unable to launch activity');
+        await new Future<Null>.delayed(const Duration(milliseconds: 1000));
+      }
+
+      final Map<String, dynamic> endData = await device.getMemoryStats(packageName);
+      data['end_total_kb'] = endData['total_kb'];
+      data['diff_total_kb'] = endData['total_kb'] - startData['total_kb'];
+
+      await device.stop(packageName);
+
+      return new TaskResult.success(data, benchmarkScoreKeys: data.keys.toList());
+    });
   }
 }
 
diff --git a/dev/devicelab/test/adb_test.dart b/dev/devicelab/test/adb_test.dart
index 82d6842353b..6cc8dc8b3fa 100644
--- a/dev/devicelab/test/adb_test.dart
+++ b/dev/devicelab/test/adb_test.dart
@@ -93,15 +93,6 @@ void main() {
         ]);
       });
     });
-
-    group('adb', () {
-      test('tap', () async {
-        await device.tap(100, 200);
-        expectLog(<CommandArgs>[
-          cmd(command: 'input', arguments: <String>['tap', '100', '200']),
-        ]);
-      });
-    });
   });
 }
 
diff --git a/examples/flutter_gallery/lib/gallery/home.dart b/examples/flutter_gallery/lib/gallery/home.dart
index e7dda503a6b..0e8826e3b46 100644
--- a/examples/flutter_gallery/lib/gallery/home.dart
+++ b/examples/flutter_gallery/lib/gallery/home.dart
@@ -363,7 +363,7 @@ class _GalleryHomeState extends State<GalleryHome> with SingleTickerProviderStat
                 ? const Text('Flutter gallery')
                 : new Text(_category.name),
             ),
-            frontHeading: widget.testMode ? null : new Container(height: 24.0),
+            frontHeading: widget.testMode ? null: new Container(height: 24.0),
             frontLayer: new AnimatedSwitcher(
               duration: _kFrontLayerSwitchDuration,
               switchOutCurve: switchOutCurve,
diff --git a/examples/flutter_gallery/test/live_smoketest.dart b/examples/flutter_gallery/test/live_smoketest.dart
index 2f080aadd9b..13afb6fad5f 100644
--- a/examples/flutter_gallery/test/live_smoketest.dart
+++ b/examples/flutter_gallery/test/live_smoketest.dart
@@ -44,7 +44,7 @@ Future<Null> main() async {
       fail('Unrecognized demo names in _kSkippedDemoTitles: $_kSkippedDemoTitles');
 
     runApp(const GalleryApp(testMode: true));
-    final _LiveWidgetController controller = new _LiveWidgetController(WidgetsBinding.instance);
+    final _LiveWidgetController controller = new _LiveWidgetController();
     for (GalleryDemoCategory category in kAllGalleryDemoCategories) {
       await controller.tap(find.text(category.name));
       for (GalleryDemo demo in kGalleryCategoryToDemos[category]) {
@@ -73,8 +73,9 @@ Future<Null> main() async {
   }
 }
 
-class _LiveWidgetController extends LiveWidgetController {
-  _LiveWidgetController(WidgetsBinding binding) : super(binding);
+class _LiveWidgetController {
+
+  final WidgetController _controller = new WidgetController(WidgetsBinding.instance);
 
   /// With [frameSync] enabled, Flutter Driver will wait to perform an action
   /// until there are no pending frames in the app under test.
@@ -106,9 +107,8 @@ class _LiveWidgetController extends LiveWidgetController {
     return finder;
   }
 
-  @override
-  Future<Null> tap(Finder finder, { int pointer }) async {
-    await tap(await _waitForElement(finder), pointer: pointer);
+  Future<Null> tap(Finder finder) async {
+    await _controller.tap(await _waitForElement(finder));
   }
 
   Future<Null> scrollIntoView(Finder finder, {double alignment}) async {
diff --git a/examples/flutter_gallery/test_driver/memory_nav.dart b/examples/flutter_gallery/test_driver/memory_nav.dart
new file mode 100644
index 00000000000..42b8e372e2d
--- /dev/null
+++ b/examples/flutter_gallery/test_driver/memory_nav.dart
@@ -0,0 +1,15 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_driver/driver_extension.dart';
+import 'package:flutter_gallery/gallery/app.dart' show GalleryApp;
+import 'package:flutter/material.dart';
+
+void main() {
+  enableFlutterDriverExtension();
+  // As in lib/main.dart: overriding https://github.com/flutter/flutter/issues/13736
+  // for better visual effect at the cost of performance.
+  MaterialPageRoute.debugEnableFadingRoutes = true; // ignore: deprecated_member_use
+  runApp(const GalleryApp(testMode: true));
+}
diff --git a/examples/flutter_gallery/test_driver/memory_nav_test.dart b/examples/flutter_gallery/test_driver/memory_nav_test.dart
new file mode 100644
index 00000000000..8771a2fc369
--- /dev/null
+++ b/examples/flutter_gallery/test_driver/memory_nav_test.dart
@@ -0,0 +1,32 @@
+import 'package:flutter_driver/flutter_driver.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('flutter gallery transitions', () {
+    FlutterDriver driver;
+    setUpAll(() async {
+      driver = await FlutterDriver.connect();
+    });
+
+    tearDownAll(() async {
+      if (driver != null)
+        await driver.close();
+    });
+
+    test('navigation', () async {
+      await driver.tap(find.text('Material'));
+
+      final SerializableFinder demoList = find.byValueKey('GalleryDemoList');
+      final SerializableFinder demoItem = find.text('Text fields');
+      await driver.scrollUntilVisible(demoList, demoItem,
+        dyScroll: -300.0,
+        alignment: 0.5,
+        timeout: const Duration(minutes: 1),
+      );
+      for (int i = 0; i < 15; i++) {
+        await driver.tap(demoItem);
+        await driver.tap(find.byTooltip('Back'));
+      }
+    });
+  });
+}
diff --git a/examples/flutter_gallery/test_memory/back_button.dart b/examples/flutter_gallery/test_memory/back_button.dart
deleted file mode 100644
index 0eeb307ec3a..00000000000
--- a/examples/flutter_gallery/test_memory/back_button.dart
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// See //dev/devicelab/bin/tasks/flutter_gallery__memory_nav.dart
-
-import 'dart:async';
-
-import 'package:flutter/material.dart';
-import 'package:flutter/scheduler.dart';
-import 'package:flutter_gallery/gallery/app.dart' show GalleryApp;
-import 'package:flutter_test/flutter_test.dart';
-
-Future<void> endOfAnimation() async {
-  do {
-    await SchedulerBinding.instance.endOfFrame;
-  } while (SchedulerBinding.instance.hasScheduledFrame);
-}
-
-int iteration = 0;
-
-class LifecycleObserver extends WidgetsBindingObserver {
-   @override
-   void didChangeAppLifecycleState(AppLifecycleState state) {
-     debugPrint('==== MEMORY BENCHMARK ==== $state ====');
-     debugPrint('This was lifecycle event number $iteration in this instance');
-   }
-}
-
-Future<void> main() async {
-  MaterialPageRoute.debugEnableFadingRoutes = true; // ignore: deprecated_member_use
-  runApp(const GalleryApp());
-  await endOfAnimation();
-  await new Future<Null>.delayed(const Duration(milliseconds: 50));
-  debugPrint('==== MEMORY BENCHMARK ==== READY ====');
-  WidgetsBinding.instance.addObserver(new LifecycleObserver());
-}
diff --git a/examples/flutter_gallery/test_memory/memory_nav.dart b/examples/flutter_gallery/test_memory/memory_nav.dart
deleted file mode 100644
index cce1dc9eeec..00000000000
--- a/examples/flutter_gallery/test_memory/memory_nav.dart
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// See //dev/devicelab/bin/tasks/flutter_gallery__memory_nav.dart
-
-import 'dart:async';
-
-import 'package:flutter/material.dart';
-import 'package:flutter/scheduler.dart';
-import 'package:flutter_gallery/gallery/app.dart' show GalleryApp;
-import 'package:flutter_test/flutter_test.dart';
-
-Future<void> endOfAnimation() async {
-  do {
-    await SchedulerBinding.instance.endOfFrame;
-  } while (SchedulerBinding.instance.hasScheduledFrame);
-}
-
-Future<void> main() async {
-  MaterialPageRoute.debugEnableFadingRoutes = true; // ignore: deprecated_member_use
-  final Completer<void> ready = new Completer<void>();
-  runApp(new GestureDetector(
-    onTap: () {
-      debugPrint('Received tap.');
-      ready.complete();
-    },
-    behavior: HitTestBehavior.opaque,
-    child: const IgnorePointer(
-      ignoring: true,
-      child: GalleryApp(testMode: true),
-    ),
-  ));
-  await SchedulerBinding.instance.endOfFrame;
-  await new Future<Null>.delayed(const Duration(milliseconds: 50));
-  debugPrint('==== MEMORY BENCHMARK ==== READY ====');
-
-  await ready.future;
-  debugPrint('Continuing...');
-
-  // remove onTap handler, enable pointer events for app
-  runApp(new GestureDetector(
-    child: const IgnorePointer(
-      ignoring: false,
-      child: GalleryApp(testMode: true),
-    ),
-  ));
-  await SchedulerBinding.instance.endOfFrame;
-
-  final WidgetController controller = new LiveWidgetController(WidgetsBinding.instance);
-
-  debugPrint('Navigating...');
-  await controller.tap(find.text('Material'));
-  await new Future<Null>.delayed(const Duration(milliseconds: 150));
-  final Finder demoList = find.byKey(const Key('GalleryDemoList'));
-  final Finder demoItem = find.text('Text fields');
-  do {
-    await controller.drag(demoList, const Offset(0.0, -300.0));
-    await new Future<Null>.delayed(const Duration(milliseconds: 20));
-  } while (!demoItem.precache());
-
-  for (int iteration = 0; iteration < 15; iteration += 1) {
-    debugPrint('Tapping... (iteration $iteration)');
-    await controller.tap(demoItem);
-    await endOfAnimation();
-    debugPrint('Backing out...');
-    await controller.tap(find.byTooltip('Back').last);
-    await endOfAnimation();
-  }
-
-  debugPrint('==== MEMORY BENCHMARK ==== DONE ====');
-}
diff --git a/packages/flutter_driver/lib/src/driver/driver.dart b/packages/flutter_driver/lib/src/driver/driver.dart
index 3626016acbf..a2dc0ad653e 100644
--- a/packages/flutter_driver/lib/src/driver/driver.dart
+++ b/packages/flutter_driver/lib/src/driver/driver.dart
@@ -447,19 +447,19 @@ class FlutterDriver {
   /// ensure the item's final position matches [alignment].
   ///
   /// The [scrollable] must locate the scrolling widget that contains [item].
-  /// Typically `find.byType('ListView')` or `find.byType('CustomScrollView')`.
+  /// Typically `find.byType('ListView') or `find.byType('CustomScrollView')`.
   ///
-  /// At least one of [dxScroll] and [dyScroll] must be non-zero.
+  /// Atleast one of [dxScroll] and [dyScroll] must be non-zero.
   ///
   /// If [item] is below the currently visible items, then specify a negative
   /// value for [dyScroll] that's a small enough increment to expose [item]
   /// without potentially scrolling it up and completely out of view. Similarly
-  /// if [item] is above, then specify a positive value for [dyScroll].
+  /// if [item] is above, then specify a positve value for [dyScroll].
   ///
-  /// If [item] is to the right of the currently visible items, then
+  /// If [item] is to the right of the the currently visible items, then
   /// specify a negative value for [dxScroll] that's a small enough increment to
   /// expose [item] without potentially scrolling it up and completely out of
-  /// view. Similarly if [item] is to the left, then specify a positive value
+  /// view. Similarly if [item] is to the left, then specify a positve value
   /// for [dyScroll].
   ///
   /// The [timeout] value should be long enough to accommodate as many scrolls
@@ -483,7 +483,7 @@ class FlutterDriver {
     // the chance to complete if the item is already onscreen; if not, scroll
     // repeatedly until we either find the item or time out.
     bool isVisible = false;
-    waitFor(item, timeout: timeout).then((Null value) { isVisible = true; });
+    waitFor(item, timeout: timeout).then((Null _) { isVisible = true; });
     await new Future<Null>.delayed(const Duration(milliseconds: 500));
     while (!isVisible) {
       await scroll(scrollable, dxScroll, dyScroll, const Duration(milliseconds: 100));
diff --git a/packages/flutter_driver/lib/src/extension/extension.dart b/packages/flutter_driver/lib/src/extension/extension.dart
index 2043ed5bd71..78584c25933 100644
--- a/packages/flutter_driver/lib/src/extension/extension.dart
+++ b/packages/flutter_driver/lib/src/extension/extension.dart
@@ -146,7 +146,7 @@ class FlutterDriverExtension {
 
   static final Logger _log = new Logger('FlutterDriverExtension');
 
-  final WidgetController _prober = new LiveWidgetController(WidgetsBinding.instance);
+  final WidgetController _prober = new WidgetController(WidgetsBinding.instance);
   final Map<String, CommandHandlerCallback> _commandHandlers = <String, CommandHandlerCallback>{};
   final Map<String, CommandDeserializerCallback> _commandDeserializers = <String, CommandDeserializerCallback>{};
   final Map<String, FinderConstructor> _finders = <String, FinderConstructor>{};
diff --git a/packages/flutter_test/lib/src/controller.dart b/packages/flutter_test/lib/src/controller.dart
index 9baea2cb9fa..e93bba422c2 100644
--- a/packages/flutter_test/lib/src/controller.dart
+++ b/packages/flutter_test/lib/src/controller.dart
@@ -15,12 +15,8 @@ import 'test_pointer.dart';
 
 /// Class that programmatically interacts with widgets.
 ///
-/// For a variant of this class suited specifically for unit tests, see
-/// [WidgetTester]. For one suitable for live tests on a device, consider
-/// [LiveWidgetController].
-///
-/// Concrete subclasses must implement the [pump] method.
-abstract class WidgetController {
+/// For a variant of this class suited specifically for unit tests, see [WidgetTester].
+class WidgetController {
   /// Creates a widget controller that uses the given binding.
   WidgetController(this.binding);
 
@@ -396,11 +392,10 @@ abstract class WidgetController {
   /// This is invoked by [flingFrom], for instance, so that the sequence of
   /// pointer events occurs over time.
   ///
-  /// The [WidgetTester] subclass implements this by deferring to the [binding].
+  /// The default implementation does nothing.
   ///
-  /// See also [SchedulerBinding.endOfFrame], which returns a future that could
-  /// be appropriate to return in the implementation of this method.
-  Future<Null> pump(Duration duration);
+  /// The [WidgetTester] subclass implements this by deferring to the [binding].
+  Future<Null> pump(Duration duration) => new Future<Null>.value(null);
 
   /// Attempts to drag the given widget by the given offset, by
   /// starting a drag in the middle of the widget.
@@ -521,20 +516,3 @@ abstract class WidgetController {
   /// the widget's render object has been laid out at least once.
   Rect getRect(Finder finder) => getTopLeft(finder) & getSize(finder);
 }
-
-/// Variant of [WidgetController] that can be used in tests running
-/// on a device.
-///
-/// This is used, for instance, by [FlutterDriver].
-class LiveWidgetController extends WidgetController {
-  /// Creates a widget controller that uses the given binding.
-  LiveWidgetController(WidgetsBinding binding) : super(binding);
-
-  @override
-  Future<Null> pump(Duration duration) async {
-    if (duration != null)
-      await new Future<void>.delayed(duration);
-    binding.scheduleFrame();
-    await binding.endOfFrame;
-  }
-}
diff --git a/packages/flutter_tools/lib/src/android/gradle.dart b/packages/flutter_tools/lib/src/android/gradle.dart
index 13162b686b2..8842503497a 100644
--- a/packages/flutter_tools/lib/src/android/gradle.dart
+++ b/packages/flutter_tools/lib/src/android/gradle.dart
@@ -360,11 +360,11 @@ Future<Null> _buildGradleProjectV2(
 
   command.add(assembleTask);
   final int exitCode = await runCommandAndStreamOutput(
-    command,
-    workingDirectory: flutterProject.android.directory.path,
-    allowReentrantFlutter: true,
-    environment: _gradleEnv,
-    filter: logger.isVerbose ? null : ndkMessageFilter,
+      command,
+      workingDirectory: flutterProject.android.directory.path,
+      allowReentrantFlutter: true,
+      environment: _gradleEnv,
+      filter: logger.isVerbose ? null : ndkMessageFilter,
   );
   status.stop();
 
diff --git a/packages/flutter_tools/lib/src/base/process.dart b/packages/flutter_tools/lib/src/base/process.dart
index 2105aa53da8..6eceade9334 100644
--- a/packages/flutter_tools/lib/src/base/process.dart
+++ b/packages/flutter_tools/lib/src/base/process.dart
@@ -302,11 +302,10 @@ String runSync(List<String> cmd, {
 
 void _traceCommand(List<String> args, { String workingDirectory }) {
   final String argsText = args.join(' ');
-  if (workingDirectory == null) {
-    printTrace('executing: $argsText');
-  } else {
-    printTrace('executing: [$workingDirectory${fs.path.separator}] $argsText');
-  }
+  if (workingDirectory == null)
+    printTrace(argsText);
+  else
+    printTrace('[$workingDirectory${fs.path.separator}] $argsText');
 }
 
 String _runWithLoggingSync(List<String> cmd, {