A free program for Android, by Solution Cat Ltd.

This Document scanner app is an all-in-one tool that provides you with the best possible scanning experience. It can convert your documents to PDF format, or you can scan and upload them to the cloud.

With this app, you can scan, edit, and convert your documents into PDFs. If you have a lot of paper documents, you can use this app to convert them into PDFs. You can edit and crop them as needed. You can also rotate them and add text to them. 

If you need to make a PDF from an image, this is the best app for you. It has a powerful image-to-text converter (OCR) that can read almost any kind of image. It can also read text from a camera or photo gallery. This app is very smart and can automatically detect the borders of the image.