I haven't tried it for live chess, but think it's great for online. It doesn't have the full functionality of being onine, no explorer mode for example, but great for reviewing the games and getting a few moves in when you're out and about away from the computer. Download it and see what you think - there's nothing to lose!
I've been wanting to download the Chess.com app, but I can't find very many positive comments (even though the overall rating is pretty good). Most of the negative comments are related to live chess. I will be playing almost exclusively online chess. How well does the app support online chess?