UB reader is a very important application in which you can use it to read all pdf file with your android device.
Such as books that are in pdf format
instead of buying you can easily download the book pdf in your android device and with the help of UB reader you can read all contain in the book.
HOW TO DOWNLOADED AND USE UB READER
. download UB reader from Google play
. install it and open it
. Tick all PDF files and click import file
. you will see all your PDF files that you have downloaded
. That's all you can now read all pdf files
See screen shot below