If you're looking for another mobile FPS to scratch that itch, check out Squad Wars: Death Division [Free], which has just released globally. The game has you playing a participant in the largest squad-based tournament in human history, organized by the mysterious billionaire Barakiel. There's a huge prize, of course, and you're one of those trying to get their hands on that sweet, sweet money. The game features an ELO rating, a league system, and skill-based matchmaking with up to 6 players per match. Talk of ELOs is nice, but hopefully Squad Wars will actually get matchmaking to work well.
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The game includes a variety of modes - deathmatch, last man standing, etc - that you can play in 1v1, 2v2, 2v2v2, and 3v3. Add to those modes 11 maps and a ton of guns, and I think it's fair to say variety won't be Squad Wars' weakness. The game is out globally now, so go check it out if mobile FPS are your thing.

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