diff --git a/README.md b/README.md
index 55b7b8a1..8bafec31 100644
--- a/README.md
+++ b/README.md
@@ -15,12 +15,29 @@
 ### Manual installation
 
 
-#### [iOS] This guide is not completed yet
+#### [iOS]
 
-1. In XCode, in the project navigator, right click `Libraries` ➜ `Add Files to [your project's name]`
-2. Go to `node_modules` ➜ `react-native-video-processing` and add `RNVideoEditor.xcodeproj`
-3. In XCode, in the project navigator, select your project. Add `libRNVideoEditor.a` to your project's `Build Phases` ➜ `Link Binary With Libraries`
-4. Run your project (`Cmd+R`)<
+1. In Xcode, click the "Add Files to <your-project-name>".
+2. Go to `node_modules` ➜ `react-native-video-processing` and add `RNVideoProcessing` directory.
+3. Make sure `RNVideoProcessing` is "under" the "top-level" and then remove `GPUImage.xcodeproj` from `RNVideoProcessing` directory.
+4. Add GPUImage.xcodeproj from `node_modules/react-native-video-processing/RNVideoProcessing` directory to your project and make sure it is "under" the "top-level":
+
+    ![Project Structure](readme_assets/project-structure.png)
+
+5. In XCode, in the project navigator, select your project.
+
+   Add
+    - CoreMedia
+    - CoreVideo
+    - OpenGLES
+    - AVFoundation
+    - QuartzCore
+    - GPUImage
+    - MobileCoreServices
+
+    to your project's `Build Phases` ➜ `Link Binary With Libraries`.
+6. import `RNVideoProcessing.h` into your `project_name-bridging-header.h`.
+4. Clean and Run your project.
 
 #### Android version is not supported yet
 
@@ -34,10 +51,18 @@ class App extends Component {
     constructor(...args) {
         super(...args);
     }
+
+    trimVideo() {
+        this.videoPlayerRef.trim(require('./videoFile.mp4'), startTime, endTime)
+            .then((newSource) => console.log(newSource))
+            .catch(console.warn)
+    }
+
     render() {
         return (
             <View style={{ flex: 1 }}>
                 <VideoPlayer
+                    ref={ref => this.videoPlayerRef = ref}
                     startTime={30} // seconds
                     endTime={120} // seconds
                     play={true} // default false
@@ -48,6 +73,9 @@ class App extends Component {
                 />
                 <Trimmer
                     source={require('./videoFile.mp4')}
+                    height={100}
+                    width={300}
+                    themeColor={'white'}
                     onChange={(e) => console.log(e.startTime, e.endTime)}
                 />
             </View>
@@ -59,4 +87,4 @@ class App extends Component {
 ##Contributing
 
 1. Please follow the eslint style guide.
-2. Please commit with `$ npm run commit`
+2. Please commit with `$ npm run commit`
\ No newline at end of file
diff --git a/lib/Trimmer/Trimmer.js b/lib/Trimmer/Trimmer.js
index 240c0edc..1333be2c 100644
--- a/lib/Trimmer/Trimmer.js
+++ b/lib/Trimmer/Trimmer.js
@@ -1,59 +1,57 @@
 import React, { PropTypes, Component } from 'react';
 import {
-  View,
   requireNativeComponent,
   DeviceEventEmitter,
   processColor
 } from 'react-native';
 import { getActualSource } from '../utils';
 const TRIMMER_COMPONENT_NAME = 'RNTrimmerView';
-const TRIM_EVENT = "VIDEO_PROCESSING_EVENT_TRIMMER";
+const TRIM_EVENT = 'VIDEO_PROCESSING_EVENT_TRIMMER';
 
 export class Trimmer extends Component {
-    static propTypes = {
-      source: PropTypes.oneOfType([PropTypes.string, PropTypes.number]).isRequired,
-      width: PropTypes.number,
-      height: PropTypes.number,
-      themeColor: PropTypes.string,
-      onChange: PropTypes.func
-  };
-
-  static defaultProps = {
-      themeColor: 'gray'
-  };
-
-  constructor(...args) {
-    super(...args);
-    this.state = {};
-    this.trimListener = null;
-  }
-
-  componentDidMount() {
-      this.trimListener = DeviceEventEmitter.addListener(TRIM_EVENT, (event) => {
-          if (typeof this.props.onChange === 'function') {
-              this.props.onChange(event);
-          }
-      });
-  }
-
-  componentWillUnmount() {
-      DeviceEventEmitter.removeListener(TRIM_EVENT, this.trimListener);
-  }
-
-
-  render() {
-      const { source, width, height, themeColor } = this.props;
-      const actualSource = getActualSource(source);
-      return (
-          <RNTrimmer
-              source={actualSource}
-              width={width}
-              height={height}
-              themeColor={processColor(themeColor).toString()}
-              pointerEvents={'box-none'}
-          />
-      );
-  }
+	static propTypes = {
+		source: PropTypes.oneOfType([PropTypes.string, PropTypes.number]).isRequired,
+		width: PropTypes.number,
+		height: PropTypes.number,
+		themeColor: PropTypes.string,
+		onChange: PropTypes.func
+	};
+
+	static defaultProps = {
+		themeColor: 'gray'
+	};
+
+	constructor(...args) {
+		super(...args);
+		this.state = {};
+		this.trimListener = null;
+	}
+
+	componentDidMount() {
+		this.trimListener = DeviceEventEmitter.addListener(TRIM_EVENT, (event) => {
+			if (typeof this.props.onChange === 'function') {
+				this.props.onChange(event);
+			}
+		});
+	}
+
+	componentWillUnmount() {
+		DeviceEventEmitter.removeListener(TRIM_EVENT, this.trimListener);
+	}
+
+	render() {
+		const { source, width, height, themeColor } = this.props;
+		const actualSource = getActualSource(source);
+		return (
+			<RNTrimmer
+				source={actualSource}
+				width={width}
+				height={height}
+				themeColor={processColor(themeColor).toString()}
+				pointerEvents={'box-none'}
+			/>
+		);
+	}
 }
 
 const RNTrimmer = requireNativeComponent(TRIMMER_COMPONENT_NAME, Trimmer);
diff --git a/lib/VideoPlayer/VideoPlayer.js b/lib/VideoPlayer/VideoPlayer.js
index 1433a6b4..4c771d9f 100644
--- a/lib/VideoPlayer/VideoPlayer.js
+++ b/lib/VideoPlayer/VideoPlayer.js
@@ -35,8 +35,9 @@ export class VideoPlayer extends Component {
 	}
 
 	trim(source, start, end) {
+		const actualSource = getActualSource(source);
 		return new Promise((resolve, reject) => {
-			RNVideoTrimmer.trim(source, start, end, (err, output) => {
+			RNVideoTrimmer.trim(actualSource, start, end, (err, output) => {
 				if (err) {
 					return reject(err);
 				}
diff --git a/readme_assets/project-structure.png b/readme_assets/project-structure.png
new file mode 100644
index 00000000..bca6584c
Binary files /dev/null and b/readme_assets/project-structure.png differ