CamScan is the good scanner app which can easily scan your images and convert them into PDF form in a single tap.

There are many advance features in it:

*Immediately detect document
Firstly, it selects image from the gallery/camera and detects document from it

*Enhance the quality
It can enhance the document quality by allowing you free hand cropping (you can change the size of cropped area) and apply different type of filters on it (grayscale, black and white)

*Obtain Texts from Image
OCR feature is also available in this application, which can obtain text from the image which is editable.

*Share scanned image
You can save and share the scanned image.

*Share PDF Files
You can also save and share the scanned images in PDF form.

*Scan QR code
You can also scan QR code from this application