Cam Scanner  is one of the best photo scanner apps that allows you to scan documents using your phone. The app is so easy to use, and it is great to work as a free app for Android phones.

All you need is to hold your phone at the right angle and use a document as a target. You can scan a file, and you can use the generated PDF document as a new page to write on.

With the built-in crop function, you can choose the location for each image. You can crop your file to a specific size and then rotate it.

You can set a color for the document in the preview, and if you're satisfied with the result, you can save it in PDF format and send it to your friends or use it as your desktop wallpaper. Furthermore, you can apply a variety of filters to the scanned documents.