Droid Scan Pro PDF apk v5.7.6 free download

Here is an app which turns your android device into portable scanner-

DROID SCAN PRO PDF

SHORT DESCRIPTION- 
Droid Scan is a mobile app that turns your phone or tablet into a portable document scanner. With Droid Scan you can transform images captured with your camera into professional multi-page PDF documents in just a few clicks.

Genius Scan+ - PDF Scanner apk v1.3.4 free download

Here is an app which turns your android into pocket scanner-

GENIUS SCAN + - PDF SCANNER

SHORT DESCRIPTION- 
Genius Scan+ is a scanner in your pocket. It enables you to quickly scan documents on the go and email the scans as JPEG or PDF with multiple pages.

Scanthing (OCR & PDF Creator) apk v2.03 free download

Here is app which let you start a paperless life-

SCANTHING (OCR & PDF CREATOR)

SHORT DESCRIPTION- 
Scanthing extracts text from pictures and documents and allows you to search for them by keywords on your phone using OCR (Optical Character Recognition) technology. It supports image cleaning and conversion to PDF, including creating keyword searchable PDFs from your image. Its the only Document Scanner you need. Scanthing supports OCR in 33 languages.