diff --git a/packages/cli/package.json b/packages/cli/package.json
index 3aeb28ab6..4ca402fd5 100644
--- a/packages/cli/package.json
+++ b/packages/cli/package.json
@@ -27,6 +27,7 @@
     "envinfo": "^5.7.0",
     "errorhandler": "^1.5.0",
     "escape-string-regexp": "^1.0.5",
+    "execa": "^1.0.0",
     "fs-extra": "^1.0.0",
     "glob": "^7.1.1",
     "graceful-fs": "^4.1.3",
@@ -55,5 +56,8 @@
   },
   "peerDependencies": {
     "react-native": "^0.57.0"
+  },
+  "devDependencies": {
+    "snapshot-diff": "^0.5.0"
   }
 }
diff --git a/packages/cli/src/upgrade/__tests__/__snapshots__/upgrade.test.js.snap b/packages/cli/src/upgrade/__tests__/__snapshots__/upgrade.test.js.snap
new file mode 100644
index 000000000..13c7caaa8
--- /dev/null
+++ b/packages/cli/src/upgrade/__tests__/__snapshots__/upgrade.test.js.snap
@@ -0,0 +1,27 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`fetches regular patch, adds remote, applies patch, installs deps, removes remote,: RnDiffApp is replaced with app name (TestApp) 1`] = `
+"Snapshot Diff:
+- First value
++ Second value
+
+@@ -1,5 +1,5 @@
+- diff --git a/RnDiffApp/android/build.gradle b/RnDiffApp/android/build.gradle
++ diff --git a/TestApp/android/build.gradle b/TestApp/android/build.gradle
+  index 85d8f2f8..a1e80854 100644
+- --- a/RnDiffApp/android/build.gradle
+- +++ b/RnDiffApp/android/build.gradle
++ --- a/TestApp/android/build.gradle
++ +++ b/TestApp/android/build.gradle
+  @@ -9,8 +9,8 @@ buildscript {
+@@ -28,6 +28,6 @@
+  
+- diff --git a/RnDiffApp/package.json b/RnDiffApp/package.json
++ diff --git a/TestApp/package.json b/TestApp/package.json
+  index 4e617645..c82829bd 100644
+- --- a/RnDiffApp/package.json
+- +++ b/RnDiffApp/package.json
++ --- a/TestApp/package.json
++ +++ b/TestApp/package.json
+  @@ -7,14 +7,14 @@"
+`;
diff --git a/packages/cli/src/upgrade/__tests__/sample.patch b/packages/cli/src/upgrade/__tests__/sample.patch
new file mode 100644
index 000000000..f5f8ef685
--- /dev/null
+++ b/packages/cli/src/upgrade/__tests__/sample.patch
@@ -0,0 +1,51 @@
+diff --git a/RnDiffApp/android/build.gradle b/RnDiffApp/android/build.gradle
+index 85d8f2f8..a1e80854 100644
+--- a/RnDiffApp/android/build.gradle
++++ b/RnDiffApp/android/build.gradle
+@@ -9,8 +9,8 @@ buildscript {
+         supportLibVersion = "27.1.1"
+     }
+     repositories {
+-        jcenter()
+         google()
++        jcenter()
+     }
+     dependencies {
+         classpath 'com.android.tools.build:gradle:3.1.4'
+@@ -23,12 +23,12 @@ buildscript {
+ allprojects {
+     repositories {
+         mavenLocal()
++        google()
+         jcenter()
+         maven {
+             // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
+             url "$rootDir/../node_modules/react-native/android"
+         }
+-        google()
+     }
+ }
+
+diff --git a/RnDiffApp/package.json b/RnDiffApp/package.json
+index 4e617645..c82829bd 100644
+--- a/RnDiffApp/package.json
++++ b/RnDiffApp/package.json
+@@ -7,14 +7,14 @@
+     "test": "jest"
+   },
+   "dependencies": {
+-    "react": "16.5.0",
+-    "react-native": "0.57.0"
++    "react": "16.6.1",
++    "react-native": "0.57.7"
+   },
+   "devDependencies": {
+     "babel-jest": "23.6.0",
+     "jest": "23.6.0",
+-    "metro-react-native-babel-preset": "0.47.1",
+-    "react-test-renderer": "16.5.0"
++    "metro-react-native-babel-preset": "0.49.2",
++    "react-test-renderer": "16.6.1"
+   },
+   "jest": {
+     "preset": "react-native"
diff --git a/packages/cli/src/upgrade/__tests__/upgrade.test.js b/packages/cli/src/upgrade/__tests__/upgrade.test.js
new file mode 100644
index 000000000..71054941f
--- /dev/null
+++ b/packages/cli/src/upgrade/__tests__/upgrade.test.js
@@ -0,0 +1,209 @@
+// @flow
+import execa from 'execa';
+import path from 'path';
+import fs from 'fs';
+import snapshotDiff from 'snapshot-diff';
+import upgrade from '../upgrade';
+import { fetch } from '../helpers';
+import logger from '../../util/logger';
+
+jest.mock('https');
+jest.mock('fs');
+jest.mock('path');
+jest.mock('execa', () => {
+  const module = jest.fn((command, args) => {
+    mockPushLog('$', 'execa', command, args);
+    if (command === 'npm' && args[3] === '--json') {
+      return Promise.resolve({
+        stdout: '{"react": "16.6.3"}',
+      });
+    }
+    return Promise.resolve({ stdout: '' });
+  });
+  return module;
+});
+jest.mock(
+  '/project/root/node_modules/react-native/package.json',
+  () => ({ name: 'react-native', version: '0.57.8' }),
+  { virtual: true }
+);
+jest.mock(
+  '/project/root/package.json',
+  () => ({ name: 'TestApp', dependencies: { 'react-native': '^0.57.8' } }),
+  { virtual: true }
+);
+jest.mock('../../util/PackageManager', () =>
+  jest.fn(() => ({
+    install: args => {
+      mockPushLog('$ yarn add', ...args);
+    },
+  }))
+);
+jest.mock('../helpers', () => ({
+  ...jest.requireActual('../helpers'),
+  fetch: jest.fn(() => Promise.resolve('patch')),
+}));
+jest.mock('../../util/logger', () => ({
+  info: jest.fn((...args) => mockPushLog('info', args)),
+  error: jest.fn((...args) => mockPushLog('error', args)),
+  warn: jest.fn((...args) => mockPushLog('warn', args)),
+  success: jest.fn((...args) => mockPushLog('success', args)),
+  log: jest.fn((...args) => mockPushLog(args)),
+}));
+
+const currentVersion = '0.57.8';
+const newVersion = '0.58.4';
+const olderVersion = '0.56.0';
+const ctx = {
+  root: '/project/root',
+  reactNativePath: '',
+};
+const opts = {
+  legacy: false,
+};
+
+const samplePatch = jest
+  .requireActual('fs')
+  .readFileSync(path.join(__dirname, './sample.patch'), 'utf8');
+
+let logs = [];
+const mockPushLog = (...args) =>
+  logs.push(args.map(x => (Array.isArray(x) ? x.join(' ') : x)).join(' '));
+const flushOutput = () => logs.join('\n');
+
+beforeEach(() => {
+  jest.clearAllMocks();
+  // $FlowFixMe
+  fs.writeFileSync = jest.fn(filename => mockPushLog('[fs] write', filename));
+  // $FlowFixMe
+  fs.unlinkSync = jest.fn((...args) => mockPushLog('[fs] unlink', args));
+  logs = [];
+});
+
+test('uses latest version of react-native when none passed', async () => {
+  await upgrade.func([], ctx, opts);
+  expect(execa).toBeCalledWith('npm', ['info', 'react-native', 'version']);
+});
+
+test('errors when invalid version passed', async () => {
+  await upgrade.func(['next'], ctx, opts);
+  expect(logger.error).toBeCalledWith(
+    'Provided version "next" is not allowed. Please pass a valid semver version'
+  );
+});
+
+test('errors when older version passed', async () => {
+  await upgrade.func([olderVersion], ctx, opts);
+  expect(logger.error).toBeCalledWith(
+    `Trying to upgrade from newer version "${currentVersion}" to older "${olderVersion}"`
+  );
+});
+
+test('warns when dependency upgrade version is in semver range', async () => {
+  await upgrade.func([currentVersion], ctx, opts);
+  expect(logger.warn).toBeCalledWith(
+    `Specified version "${currentVersion}" is already installed in node_modules and it satisfies "^0.57.8" semver range. No need to upgrade`
+  );
+});
+
+test('fetches empty patch and installs deps', async () => {
+  (fetch: any).mockImplementation(() => Promise.resolve(''));
+  await upgrade.func([newVersion], ctx, opts);
+  expect(flushOutput()).toMatchInlineSnapshot(`
+"info Fetching diff between v0.57.8 and v0.58.4...
+info Diff has no changes to apply, proceeding further
+warn Continuing after failure. Most of the files are upgraded but you will need to deal with some conflicts manually
+info Installing react-native@0.58.4 and its peer dependencies...
+$ execa npm info react-native@0.58.4 peerDependencies --json
+$ yarn add react-native@0.58.4 react@16.6.3
+$ execa git add package.json
+$ execa git add yarn.lock
+$ execa git add package-lock.json
+success Upgraded React Native to v0.58.4 🎉. Now you can review and commit the changes"
+`);
+});
+
+test('fetches regular patch, adds remote, applies patch, installs deps, removes remote,', async () => {
+  (fetch: any).mockImplementation(() => Promise.resolve(samplePatch));
+  await upgrade.func([newVersion], ctx, opts);
+  expect(flushOutput()).toMatchInlineSnapshot(`
+"info Fetching diff between v0.57.8 and v0.58.4...
+[fs] write tmp-upgrade-rn.patch
+$ execa git remote add tmp-rn-diff-purge https://github.com/pvinis/rn-diff-purge.git
+$ execa git fetch --no-tags tmp-rn-diff-purge
+$ execa git apply --check tmp-upgrade-rn.patch --exclude=package.json -p2 --3way
+info Applying diff...
+$ execa git apply tmp-upgrade-rn.patch --exclude=package.json -p2 --3way
+[fs] unlink tmp-upgrade-rn.patch
+info Installing react-native@0.58.4 and its peer dependencies...
+$ execa npm info react-native@0.58.4 peerDependencies --json
+$ yarn add react-native@0.58.4 react@16.6.3
+$ execa git add package.json
+$ execa git add yarn.lock
+$ execa git add package-lock.json
+info Running \\"git status\\" to check what changed...
+$ execa git status
+$ execa git remote remove tmp-rn-diff-purge
+success Upgraded React Native to v0.58.4 🎉. Now you can review and commit the changes"
+`);
+
+  expect(
+    snapshotDiff(samplePatch, fs.writeFileSync.mock.calls[0][1], {
+      contextLines: 1,
+    })
+  ).toMatchSnapshot('RnDiffApp is replaced with app name (TestApp)');
+});
+
+test('cleans up if patching fails,', async () => {
+  (fetch: any).mockImplementation(() => Promise.resolve(samplePatch));
+  (execa: any).mockImplementation((command, args) => {
+    mockPushLog('$', 'execa', command, args);
+    if (command === 'npm' && args[3] === '--json') {
+      return Promise.resolve({
+        stdout: '{"react": "16.6.3"}',
+      });
+    }
+    if (command === 'git' && args[0] === 'apply') {
+      // eslint-disable-next-line prefer-promise-reject-errors
+      return Promise.reject({
+        code: 1,
+        stderr: 'error: .flowconfig: does not exist in index\n',
+      });
+    }
+    return Promise.resolve({ stdout: '' });
+  });
+
+  try {
+    await upgrade.func([newVersion], ctx, opts);
+  } catch (error) {
+    expect(error.message).toBe(
+      'Upgrade failed. Please see the messages above for details'
+    );
+  }
+
+  expect(flushOutput()).toMatchInlineSnapshot(`
+"info Fetching diff between v0.57.8 and v0.58.4...
+[fs] write tmp-upgrade-rn.patch
+$ execa git remote add tmp-rn-diff-purge https://github.com/pvinis/rn-diff-purge.git
+$ execa git fetch --no-tags tmp-rn-diff-purge
+$ execa git apply --check tmp-upgrade-rn.patch --exclude=package.json -p2 --3way
+info Applying diff (excluding: package.json, .flowconfig)...
+$ execa git apply tmp-upgrade-rn.patch --exclude=package.json --exclude=.flowconfig -p2 --3way
+error: .flowconfig: does not exist in index
+error Automatically applying diff failed
+info Here's the diff we tried to apply: https://github.com/pvinis/rn-diff-purge/compare/version/0.57.8...version/0.58.4
+info You may find release notes helpful: https://github.com/facebook/react-native/releases/tag/v0.58.4
+[fs] unlink tmp-upgrade-rn.patch
+warn Continuing after failure. Most of the files are upgraded but you will need to deal with some conflicts manually
+info Installing react-native@0.58.4 and its peer dependencies...
+$ execa npm info react-native@0.58.4 peerDependencies --json
+$ yarn add react-native@0.58.4 react@16.6.3
+$ execa git add package.json
+$ execa git add yarn.lock
+$ execa git add package-lock.json
+info Running \\"git status\\" to check what changed...
+$ execa git status
+$ execa git remote remove tmp-rn-diff-purge
+warn Please run \\"git diff\\" to review the conflicts and resolve them"
+`);
+});
diff --git a/packages/cli/src/upgrade/helpers.js b/packages/cli/src/upgrade/helpers.js
new file mode 100644
index 000000000..e40353588
--- /dev/null
+++ b/packages/cli/src/upgrade/helpers.js
@@ -0,0 +1,17 @@
+// @flow
+import https from 'https';
+
+export const fetch = (url: string) =>
+  new Promise<string>((resolve, reject) => {
+    const request = https.get(url, response => {
+      if (response.statusCode < 200 || response.statusCode > 299) {
+        reject(
+          new Error(`Failed to load page, status code: ${response.statusCode}`)
+        );
+      }
+      const body = [];
+      response.on('data', chunk => body.push(chunk));
+      response.on('end', () => resolve(body.join('')));
+    });
+    request.on('error', err => reject(err));
+  });
diff --git a/packages/cli/src/upgrade/legacyUpgrade.js b/packages/cli/src/upgrade/legacyUpgrade.js
new file mode 100644
index 000000000..cd601b784
--- /dev/null
+++ b/packages/cli/src/upgrade/legacyUpgrade.js
@@ -0,0 +1,154 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ * @flow
+ */
+
+import fs from 'fs';
+import path from 'path';
+import semver from 'semver';
+import type { ContextT } from '../core/types.flow';
+import logger from '../util/logger';
+import copyProjectTemplateAndReplace from '../generator/copyProjectTemplateAndReplace';
+
+/**
+ * Migrate application to a new version of React Native.
+ * See http://facebook.github.io/react-native/docs/upgrading.html
+ */
+function validateAndUpgrade(argv: Array<string>, ctx: ContextT) {
+  const projectDir = ctx.root;
+
+  const packageJSON = JSON.parse(
+    fs.readFileSync(path.resolve(projectDir, 'package.json'), 'utf8')
+  );
+
+  warn(
+    'You should consider using the new upgrade tool based on Git. It ' +
+      'makes upgrades easier by resolving most conflicts automatically.\n' +
+      'To use it:\n' +
+      '- Go back to the old version of React Native\n' +
+      '- Run "npm install -g react-native-git-upgrade"\n' +
+      '- Run "react-native-git-upgrade"\n' +
+      'See https://facebook.github.io/react-native/docs/upgrading.html'
+  );
+
+  const projectName = packageJSON.name;
+  if (!projectName) {
+    warn(
+      'Your project needs to have a name, declared in package.json, ' +
+        'such as "name": "AwesomeApp". Please add a project name. Aborting.'
+    );
+    return;
+  }
+
+  const version = packageJSON.dependencies['react-native'];
+  if (!version) {
+    warn(
+      'Your "package.json" file doesn\'t seem to declare "react-native" as ' +
+        'a dependency. Nothing to upgrade. Aborting.'
+    );
+    return;
+  }
+
+  if (version === 'latest' || version === '*') {
+    warn(
+      'Some major releases introduce breaking changes.\n' +
+        'Please use a caret version number in your "package.json" file \n' +
+        'to avoid breakage. Use e.g. react-native: ^0.38.0. Aborting.'
+    );
+    return;
+  }
+
+  const installed = JSON.parse(
+    fs.readFileSync(
+      path.resolve(projectDir, 'node_modules/react-native/package.json'),
+      'utf8'
+    )
+  );
+
+  if (!semver.satisfies(installed.version, version)) {
+    warn(
+      'react-native version in "package.json" doesn\'t match ' +
+        'the installed version in "node_modules".\n' +
+        'Try running "npm install" to fix this. Aborting.'
+    );
+    return;
+  }
+
+  const v = version.replace(/^(~|\^|=)/, '').replace(/x/i, '0');
+
+  if (!semver.valid(v)) {
+    warn(
+      "A valid version number for 'react-native' is not specified in your " +
+        "'package.json' file. Aborting."
+    );
+    return;
+  }
+
+  logger.info(
+    `Upgrading project to react-native v${installed.version}\n` +
+      `Check out the release notes and breaking changes: ` +
+      `https://github.com/facebook/react-native/releases/tag/v${semver.major(
+        v
+      )}.${semver.minor(v)}.0`
+  );
+
+  // >= v0.21.0, we require react to be a peer dependency
+  if (semver.gte(v, '0.21.0') && !packageJSON.dependencies.react) {
+    warn(
+      'Your "package.json" file doesn\'t seem to have "react" as a dependency.\n' +
+        '"react" was changed from a dependency to a peer dependency in react-native v0.21.0.\n' +
+        'Therefore, it\'s necessary to include "react" in your project\'s dependencies.\n' +
+        'Please run "npm install --save react", then re-run "react-native upgrade".\n'
+    );
+    return;
+  }
+
+  if (semver.satisfies(v, '~0.26.0')) {
+    warn(
+      'React Native 0.26 introduced some breaking changes to the native files on iOS. You can\n' +
+        'perform them manually by checking the release notes or use "rnpm" ' +
+        'to do it automatically.\n' +
+        'Just run:\n' +
+        '"npm install -g rnpm && npm install rnpm-plugin-upgrade@0.26 --save-dev", ' +
+        'then run "rnpm upgrade".'
+    );
+  }
+
+  upgradeProjectFiles(projectDir, projectName);
+
+  logger.info(
+    `Successfully upgraded this project to react-native v${installed.version}`
+  );
+}
+
+/**
+ * Once all checks passed, upgrade the project files.
+ */
+function upgradeProjectFiles(projectDir, projectName) {
+  // Just overwrite
+  copyProjectTemplateAndReplace(
+    path.dirname(require.resolve('react-native/template')),
+    projectDir,
+    projectName,
+    { upgrade: true }
+  );
+}
+
+function warn(message) {
+  logger.warn(message);
+}
+
+const upgradeCommand = {
+  name: 'upgrade',
+  description:
+    "upgrade your app's template files to the latest version; run this after " +
+    'updating the react-native version in your package.json and running npm install',
+  func: validateAndUpgrade,
+};
+
+export default upgradeCommand;
diff --git a/packages/cli/src/upgrade/upgrade.js b/packages/cli/src/upgrade/upgrade.js
index cd601b784..e5f7e863c 100644
--- a/packages/cli/src/upgrade/upgrade.js
+++ b/packages/cli/src/upgrade/upgrade.js
@@ -1,154 +1,279 @@
-/**
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- *
- * @format
- * @flow
- */
-
-import fs from 'fs';
+// @flow
+/* eslint-disable consistent-return */
 import path from 'path';
+import fs from 'fs';
+import chalk from 'chalk';
 import semver from 'semver';
+import execa from 'execa';
 import type { ContextT } from '../core/types.flow';
 import logger from '../util/logger';
-import copyProjectTemplateAndReplace from '../generator/copyProjectTemplateAndReplace';
+import PackageManager from '../util/PackageManager';
+import { fetch } from './helpers';
+import legacyUpgrade from './legacyUpgrade';
 
-/**
- * Migrate application to a new version of React Native.
- * See http://facebook.github.io/react-native/docs/upgrading.html
- */
-function validateAndUpgrade(argv: Array<string>, ctx: ContextT) {
-  const projectDir = ctx.root;
+type FlagsT = {
+  legacy: boolean,
+};
 
-  const packageJSON = JSON.parse(
-    fs.readFileSync(path.resolve(projectDir, 'package.json'), 'utf8')
-  );
+const rnDiffPurgeUrl = 'https://github.com/pvinis/rn-diff-purge';
 
-  warn(
-    'You should consider using the new upgrade tool based on Git. It ' +
-      'makes upgrades easier by resolving most conflicts automatically.\n' +
-      'To use it:\n' +
-      '- Go back to the old version of React Native\n' +
-      '- Run "npm install -g react-native-git-upgrade"\n' +
-      '- Run "react-native-git-upgrade"\n' +
-      'See https://facebook.github.io/react-native/docs/upgrading.html'
-  );
+const getLatestRNVersion = async (): Promise<string> => {
+  logger.info('No version passed. Fetching latest...');
+  const { stdout } = await execa('npm', ['info', 'react-native', 'version']);
+  return stdout;
+};
+
+const getRNPeerDeps = async (
+  version: string
+): Promise<{ [key: string]: string }> => {
+  const { stdout } = await execa('npm', [
+    'info',
+    `react-native@${version}`,
+    'peerDependencies',
+    '--json',
+  ]);
+
+  return JSON.parse(stdout);
+};
+
+const getPatch = async (currentVersion, newVersion, projectDir) => {
+  let patch;
 
-  const projectName = packageJSON.name;
-  if (!projectName) {
-    warn(
-      'Your project needs to have a name, declared in package.json, ' +
-        'such as "name": "AwesomeApp". Please add a project name. Aborting.'
+  const rnDiffAppName = 'RnDiffApp';
+  const { name } = require(path.join(projectDir, 'package.json'));
+
+  logger.info(`Fetching diff between v${currentVersion} and v${newVersion}...`);
+
+  try {
+    patch = await fetch(
+      `${rnDiffPurgeUrl}/compare/version/${currentVersion}...version/${newVersion}.diff`
     );
-    return;
+  } catch (error) {
+    logger.error(
+      `Failed to fetch diff for react-native@${newVersion}. Maybe it's not released yet?`
+    );
+    logger.info(
+      `For available releases to diff see: https://github.com/pvinis/rn-diff-purge#version-changes`
+    );
+    return null;
   }
 
-  const version = packageJSON.dependencies['react-native'];
-  if (!version) {
-    warn(
-      'Your "package.json" file doesn\'t seem to declare "react-native" as ' +
-        'a dependency. Nothing to upgrade. Aborting.'
+  return patch
+    .replace(new RegExp(rnDiffAppName, 'g'), name)
+    .replace(new RegExp(rnDiffAppName.toLowerCase(), 'g'), name.toLowerCase());
+};
+
+const getVersionToUpgradeTo = async (argv, currentVersion, projectDir) => {
+  const newVersion = argv[0]
+    ? semver.valid(argv[0]) ||
+      (semver.coerce(argv[0]) ? semver.coerce(argv[0]).version : null)
+    : await getLatestRNVersion();
+
+  if (!newVersion) {
+    logger.error(
+      `Provided version "${
+        argv[0]
+      }" is not allowed. Please pass a valid semver version`
     );
-    return;
+    return null;
   }
 
-  if (version === 'latest' || version === '*') {
-    warn(
-      'Some major releases introduce breaking changes.\n' +
-        'Please use a caret version number in your "package.json" file \n' +
-        'to avoid breakage. Use e.g. react-native: ^0.38.0. Aborting.'
+  if (currentVersion > newVersion) {
+    logger.error(
+      `Trying to upgrade from newer version "${currentVersion}" to older "${newVersion}"`
     );
-    return;
+    return null;
   }
+  if (currentVersion === newVersion) {
+    const {
+      dependencies: { 'react-native': version },
+    } = require(path.join(projectDir, 'package.json'));
 
-  const installed = JSON.parse(
-    fs.readFileSync(
-      path.resolve(projectDir, 'node_modules/react-native/package.json'),
-      'utf8'
-    )
-  );
-
-  if (!semver.satisfies(installed.version, version)) {
-    warn(
-      'react-native version in "package.json" doesn\'t match ' +
-        'the installed version in "node_modules".\n' +
-        'Try running "npm install" to fix this. Aborting.'
+    if (semver.satisfies(newVersion, version)) {
+      logger.warn(
+        `Specified version "${newVersion}" is already installed in node_modules and it satisfies "${version}" semver range. No need to upgrade`
+      );
+      return null;
+    }
+    logger.error(
+      `Dependency mismatch. Specified version "${newVersion}" is already installed in node_modules and it doesn't satisfy "${version}" semver range of your "react-native" dependency. Please re-install your dependencies`
     );
-    return;
+    return null;
   }
 
-  const v = version.replace(/^(~|\^|=)/, '').replace(/x/i, '0');
+  return newVersion;
+};
 
-  if (!semver.valid(v)) {
-    warn(
-      "A valid version number for 'react-native' is not specified in your " +
-        "'package.json' file. Aborting."
+const installDeps = async (newVersion, projectDir, patchSuccess) => {
+  if (!patchSuccess) {
+    logger.warn(
+      'Continuing after failure. Most of the files are upgraded but you will need to deal with some conflicts manually'
     );
-    return;
   }
-
   logger.info(
-    `Upgrading project to react-native v${installed.version}\n` +
-      `Check out the release notes and breaking changes: ` +
-      `https://github.com/facebook/react-native/releases/tag/v${semver.major(
-        v
-      )}.${semver.minor(v)}.0`
+    `Installing react-native@${newVersion} and its peer dependencies...`
   );
+  const peerDeps = await getRNPeerDeps(newVersion);
+  const pm = new PackageManager({ projectDir });
+  const deps = [
+    `react-native@${newVersion}`,
+    ...Object.keys(peerDeps).map(module => `${module}@${peerDeps[module]}`),
+  ];
+  await pm.install(deps, { silent: true });
+  await execa('git', ['add', 'package.json']);
+  try {
+    await execa('git', ['add', 'yarn.lock']);
+  } catch (error) {
+    // ignore
+  }
+  try {
+    await execa('git', ['add', 'package-lock.json']);
+  } catch (error) {
+    // ignore
+  }
+};
+
+const applyPatch = async (
+  currentVersion: string,
+  newVersion: string,
+  tmpPatchFile: string
+) => {
+  let filesToExclude = ['package.json'];
+  try {
+    try {
+      const excludes = filesToExclude.map(e => `--exclude=${e}`);
+      await execa('git', [
+        'apply',
+        '--check',
+        tmpPatchFile,
+        ...excludes,
+        '-p2',
+        '--3way',
+      ]);
+      logger.info(`Applying diff...`);
+    } catch (error) {
+      filesToExclude = [
+        ...filesToExclude,
+        ...error.stderr
+          .split('\n')
+          .filter(x => x.includes('does not exist in index'))
+          .map(x => x.replace(/^error: (.*): does not exist in index$/, '$1')),
+      ].filter(Boolean);
 
-  // >= v0.21.0, we require react to be a peer dependency
-  if (semver.gte(v, '0.21.0') && !packageJSON.dependencies.react) {
-    warn(
-      'Your "package.json" file doesn\'t seem to have "react" as a dependency.\n' +
-        '"react" was changed from a dependency to a peer dependency in react-native v0.21.0.\n' +
-        'Therefore, it\'s necessary to include "react" in your project\'s dependencies.\n' +
-        'Please run "npm install --save react", then re-run "react-native upgrade".\n'
+      logger.info(`Applying diff (excluding: ${filesToExclude.join(', ')})...`);
+    } finally {
+      const excludes = filesToExclude.map(e => `--exclude=${e}`);
+      await execa('git', ['apply', tmpPatchFile, ...excludes, '-p2', '--3way']);
+    }
+  } catch (error) {
+    if (error.stderr) {
+      logger.log(`${chalk.dim(error.stderr.trim())}`);
+    }
+    logger.error('Automatically applying diff failed');
+    logger.info(
+      `Here's the diff we tried to apply: ${rnDiffPurgeUrl}/compare/version/${currentVersion}...version/${newVersion}`
     );
+    logger.info(
+      `You may find release notes helpful: https://github.com/facebook/react-native/releases/tag/v${newVersion}`
+    );
+    return false;
+  }
+  return true;
+};
+
+/**
+ * Upgrade application to a new version of React Native.
+ */
+async function upgrade(argv: Array<string>, ctx: ContextT, args: FlagsT) {
+  if (args.legacy) {
+    return legacyUpgrade.func(argv, ctx);
+  }
+  const rnDiffGitAddress = `https://github.com/pvinis/rn-diff-purge.git`;
+  const tmpRemote = 'tmp-rn-diff-purge';
+  const tmpPatchFile = 'tmp-upgrade-rn.patch';
+  const projectDir = ctx.root;
+  const { version: currentVersion } = require(path.join(
+    projectDir,
+    'node_modules/react-native/package.json'
+  ));
+
+  const newVersion = await getVersionToUpgradeTo(
+    argv,
+    currentVersion,
+    projectDir
+  );
+
+  if (!newVersion) {
     return;
   }
 
-  if (semver.satisfies(v, '~0.26.0')) {
-    warn(
-      'React Native 0.26 introduced some breaking changes to the native files on iOS. You can\n' +
-        'perform them manually by checking the release notes or use "rnpm" ' +
-        'to do it automatically.\n' +
-        'Just run:\n' +
-        '"npm install -g rnpm && npm install rnpm-plugin-upgrade@0.26 --save-dev", ' +
-        'then run "rnpm upgrade".'
+  const patch = await getPatch(currentVersion, newVersion, projectDir);
+
+  if (patch === null) {
+    return;
+  }
+
+  if (patch === '') {
+    logger.info('Diff has no changes to apply, proceeding further');
+    await installDeps(newVersion, projectDir);
+    logger.success(
+      `Upgraded React Native to v${newVersion} 🎉. Now you can review and commit the changes`
     );
+    return;
   }
 
-  upgradeProjectFiles(projectDir, projectName);
+  let patchSuccess;
 
-  logger.info(
-    `Successfully upgraded this project to react-native v${installed.version}`
-  );
-}
+  try {
+    fs.writeFileSync(tmpPatchFile, patch);
+    await execa('git', ['remote', 'add', tmpRemote, rnDiffGitAddress]);
+    await execa('git', ['fetch', '--no-tags', tmpRemote]);
+    patchSuccess = await applyPatch(currentVersion, newVersion, tmpPatchFile);
+    if (!patchSuccess) {
+      return;
+    }
+  } catch (error) {
+    throw new Error(error.stderr || error);
+  } finally {
+    try {
+      fs.unlinkSync(tmpPatchFile);
+    } catch (e) {
+      // ignore
+    }
+    await installDeps(newVersion, projectDir, patchSuccess);
+    logger.info('Running "git status" to check what changed...');
+    await execa('git', ['status'], { stdio: 'inherit' });
+    await execa('git', ['remote', 'remove', tmpRemote]);
 
-/**
- * Once all checks passed, upgrade the project files.
- */
-function upgradeProjectFiles(projectDir, projectName) {
-  // Just overwrite
-  copyProjectTemplateAndReplace(
-    path.dirname(require.resolve('react-native/template')),
-    projectDir,
-    projectName,
-    { upgrade: true }
-  );
-}
+    if (!patchSuccess) {
+      logger.warn(
+        'Please run "git diff" to review the conflicts and resolve them'
+      );
+      // eslint-disable-next-line no-unsafe-finally
+      throw new Error(
+        'Upgrade failed. Please see the messages above for details'
+      );
+    }
+  }
 
-function warn(message) {
-  logger.warn(message);
+  logger.success(
+    `Upgraded React Native to v${newVersion} 🎉. Now you can review and commit the changes`
+  );
 }
 
 const upgradeCommand = {
-  name: 'upgrade',
+  name: 'upgrade [version]',
   description:
-    "upgrade your app's template files to the latest version; run this after " +
-    'updating the react-native version in your package.json and running npm install',
-  func: validateAndUpgrade,
+    "Upgrade your app's template files to the specified or latest npm version using `rn-diff-purge` project. Only valid semver versions are allowed.",
+  func: upgrade,
+  options: [
+    {
+      command: '--legacy',
+      description:
+        "Legacy implementation. Upgrade your app's template files to the latest version; run this after " +
+        'updating the react-native version in your package.json and running npm install',
+    },
+  ],
 };
 
 export default upgradeCommand;
diff --git a/packages/cli/src/util/PackageManager.js b/packages/cli/src/util/PackageManager.js
index 3c3d963aa..a586dd3c9 100644
--- a/packages/cli/src/util/PackageManager.js
+++ b/packages/cli/src/util/PackageManager.js
@@ -14,8 +14,10 @@ export default class PackageManager {
     this.options = options;
   }
 
-  executeCommand(command: string) {
-    return execSync(command, { stdio: 'inherit' });
+  executeCommand(command: string, options?: { silent: boolean }) {
+    return execSync(command, {
+      stdio: options && options.silent ? 'pipe' : 'inherit',
+    });
   }
 
   shouldCallYarn() {
@@ -26,11 +28,12 @@ export default class PackageManager {
     );
   }
 
-  install(packageNames: Array<string>) {
+  install(packageNames: Array<string>, options?: { silent: boolean }) {
     return this.shouldCallYarn()
-      ? this.executeCommand(`yarn add ${packageNames.join(' ')}`)
+      ? this.executeCommand(`yarn add ${packageNames.join(' ')}`, options)
       : this.executeCommand(
-          `npm install ${packageNames.join(' ')} --save --save-exact`
+          `npm install ${packageNames.join(' ')} --save --save-exact`,
+          options
         );
   }
 
diff --git a/packages/cli/src/util/logger.js b/packages/cli/src/util/logger.js
index 1f0442612..35aeff681 100644
--- a/packages/cli/src/util/logger.js
+++ b/packages/cli/src/util/logger.js
@@ -40,5 +40,3 @@ export default {
   debug,
   log,
 };
-
-// export { info, warn, error, debug };
diff --git a/yarn.lock b/yarn.lock
index c6132c147..157ce3e37 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3293,6 +3293,7 @@ execa@^0.7.0:
 execa@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/execa/-/execa-1.0.0.tgz#c6236a5bb4df6d6f15e88e7f017798216749ddd8"
+  integrity sha512-adbxcyWV46qiHyvSp50TKt05tB4tK3HcmF7/nxfAdhnox83seTDbwnaqKO4sXRy7roHAIFqJP/Rw/AuEbX61LA==
   dependencies:
     cross-spawn "^6.0.0"
     get-stream "^4.0.0"
@@ -7366,6 +7367,16 @@ snapdragon@^0.8.1:
     source-map-resolve "^0.5.0"
     use "^3.1.0"
 
+snapshot-diff@^0.5.0:
+  version "0.5.0"
+  resolved "https://registry.yarnpkg.com/snapshot-diff/-/snapshot-diff-0.5.0.tgz#f67f4441f0fed806ad759f937112cda8ba78ff2b"
+  integrity sha512-mDCiZCCPQb4JP8iD8+WRNo5snbcveQqmcm0uRiKedPn+8aIKhp1gvu8BQ3KE28XFT9fI0FChkMIr5zuQdYHlRw==
+  dependencies:
+    jest-diff "^24.0.0"
+    jest-snapshot "^24.0.0"
+    pretty-format "^24.0.0"
+    strip-ansi "^5.0.0"
+
 socks-proxy-agent@^4.0.0:
   version "4.0.1"
   resolved "https://registry.yarnpkg.com/socks-proxy-agent/-/socks-proxy-agent-4.0.1.tgz#5936bf8b707a993079c6f37db2091821bffa6473"