When I read ASOIAF, I used the free wiki,
http://awoiaf.westeros.org/, which is perfectly fine. It has character and chapter summaries.
The app, which requires an in-app purchase of $5 to be truly complete, has the advantage of being sanctioned by GRRM himself and dispels some of the crazy crackpot theories that the inconsistencies in his books bought to life on the world wide internets series of tubes.
The big advantage of this app is the spoiler protection. When I used the free wiki, I kept spoiling myself, but that didn't bother me that much.
And what, no Android version? Bah. Winter is coming. Literally.
March 31st... People will die.