This Image cropper is based on the gl-react-native library

npm i -S react-native-image-cropper 

or

yarn add react-native-image-cropper 

• gl-react You need to install gl-react. npm i -S gl-react
• gl-react-native You need to install gl-react-native and link the repo in RN. npm i -S gl-react-native & rnpm link
• react-native Android requires you to have RN 0.28 or higher!

• image (required): uri to image that should be cropped.
• cropHeight (required): height of the image in cropped size.
• cropWidth (required): width of the image in cropped size.
• zoom: range 0 - 100 setting zoom value. where 100 = full zoom. (default: 0)
• maxZoom: max zoom value, should be bigger than minZoom value (default: 100)
• minZoom: min zoom value, should be smaller than maxZoom value (default: 0)
• panToMove: Use pan to move image? (default: true)
• pinchToZoom Use pinch to zoom image? (default: true)
• quality: a value from 0 to 1 to describe the quality of the snapshot. 0 means 0% (most compressed) and 1 means 100% (best quality). (default: 1)
• type: the file type default value is "png", "jpg" is also supported. Refer to implementations to see more supported values. (default: jpg)
• format: the format of the output. Supported values: "base64", "file". (default: base64)
• filePath: if format is "file", the path to write the image to (default: "")
• pixelRatio: the pixel ratio to use for the rendering. By default the screen pixel scale will be used.

• crop(): returns a base64 encoded image.

... import {ImageCrop} from 'react-native-image-cropper' ... render() { return ( <View> <ImageCrop ref={'cropper'} image={this.state.image} cropHeight={this.state.height} cropWidth={this.state.width} zoom={this.state.zoom} maxZoom={80} minZoom={20} panToMove={true} pinchToZoom={true} /> <Text onPress={this.capture()}>Capture()</Text> </View> ) } capture(){ this.refs.cropper.crop() .then(base64 => console.log(base64)) } ...