Payback 2 arrived on the App Store late last year. It's the sequel to a game called Payback that was sort of a Grand Theft Auto for iOS (before Grand Theft Auto for iOS was actually released). Payback 2 added online multiplayer and a new "custom mode," and as of today, it has gone free-to-play, which means you can now pick it up for zero dollars.
The game's seen plenty of updates since its initial release. Just recently, the controls were tuned up, and plenty of bugs have been fixed and extra options added in. By going free, the dev tells us, Payback 2 should attract an influx of new players, which means the multiplayer modes should be well-populated and ready to go. If you haven't given Payback 2 a try, now's the best time to do it.