MOBAs have taken over a huge slice of the online multiplayer space, especially on mobile.
Back up a second. What exactly is a MOBA? We can tell you that it stands for Multiplayer Online Battle Arena, and that it typically combines competitive real time strategy gameplay with a more honed, action-focused tone.
Other than that, developers have take the MOBA is so many directions, it's hard to pin down exactly what one constitutes.
Among this list of top mobile MOBAs, you'll find elements of card battling, some turn-based tactics, and even a little platforming. The MOBA genre is basically wide open to interpretation, which makes it a pretty exciting place to be.