Some time ago I mentioned a custom camera component that uses OpenCV to scan documents.
Here’s another open source camera component submitted by Maximilian Mackh with built-in cropping, document edge detection and perspective correction called IPDFCameraViewController that is the spiritual successor to MAImagePickerController.
IPDFImagePickerController does not use any external libraries, and uses only the iOS SDK – namely AVFoundation, CoreMedia, CoreVideo, CoreImage and GLKit.
Here’s an image from the readme showing IPDFCameraViewController in action.
You can find IPDFCameraViewController on Github here.
A nice camera component for anyone looking to incorporate document scanning into an app.