Gather round, armchair SEALs: Gameloft has got another military magnum opus for you. Modern Combat 4: Zero Hour is available now on the Play Store for seven bones, and purports to work with Android 2.3 and up. But since this series tends to push the boundaries of mobile graphical power (if not originality,) you'll probably need a relatively new Android device to run it well. You'll also need a good bit of space - it weighs in at nearly 2GB. 8GB Nexus 7 and Nexus 4 owners, clear up some room.
The standard gung-ho FPS tropes are present: single-player mode with squad-based combat (heavily influenced by Black Ops 2, by the look of it) and online team-based combat.