PDF Reader Pro provides you the best signing experience on Android.

 1. Enter the reading page, and tap  ; 

 2. Click + to create a new signature; Directly sign on your screen;

 3. Or you can add an image signature by tapping  ;

 4. Then click Done, and insert it into the file by clicking Sign Here;

 5. If you want to delete the signature, just click and choose Clear Signature.