I've had a chance to play around a bit with Fates Forever (FF), the new MOBA on iOS. And I have to say that even though I am not traditionally a MOBA fan, FF really pulled me in. The game is dead simple to learn and play, the characters are interesting (even if they are a bit cartoonish), and it looks fantastic.
My only real criticism of it is that the maps are not that interesting. I realize you need to have dedicated channels for the players to run, and can't get too overly complicated with the environments, but I would prefer to see more variety.
I'm not likely to be playing League of Legends or DOTA 2 anytime soon, but Fates Forever is definitely worth taking a look at if you want to get the feel for that kind of game but don't want to spend hundreds of hours playing. FF is definitely something you can pick up, play for an hour, and put back down.