[sagher]

Previously i have a Amazon kindle E-reader which gifted by my uncle from USA. but my child mess with it and the result is broken.
So i have some experience to use some Apps to read E-Book.
The most Flagship Apps are.
Kindle app by Amazon
Google Play Books by google (Android)
Apple Books by Apple Corp. (iOS)

So the other then these
"Barnes & Noble Nook" has almost same features like apple or google. and also have app for both platforms.
"Kobbo" and "Libby" also has same in working. but i am not quit sure about AD visibility of these.
"FB READER" has some colourful UI and eye loving interface to read book/magazine.
Every App has concern to the format and availability of books associate with.
Mostly my end is to get a PDF file and read on PDF Reader on my smartphone.
I wish you got one of good from above mention.