I've probably mentioned this game before, possibly when it had a different name. But it's finally out in North America now and seems to be doing pretty well.
Short version is this game is essentially League of Legends but pared down enough to make matches generally a bit shorter (on average around 15 minutes). I've tried most of the major mobile MOBAs but this is the one that has stuck with me. Some of the others have different play mechanics and/or more interesting/unique characters, but this one seems to have done the best re-creating the LoL feel, but fully playable even on a phone. Definitely a tough accomplishment.
One of the nicest things is matches load up almost immediately, hopefully the playerbase stays with it. You still have some of the annoying problems with AFKers and drops, etc. but it seems like for the most part it's much less than LoL had even after a couple of years. Again, hopefully a trend that will last.
If you decide to give it a go, feel free to add me as "rittchard" in game