Woah, people are saying this game is really bad? To be honest, I enjoyed playing this game. It seems people's major complaints are about the controls, but even in there current state they're not that bad. It took me a while to realize this, but the upper right button isn't to activate the scope on your gun. It's primary purpose is an auto-aim feature. It points your gun right at the enemy closest to you. Also, if you're swiping around it's easiest closer to the middle of the screen. I agree the sensitivity of the controls should be turned down I bit, but overall I don't mind them at all.
I like how this game has somewhat of a story, it's not just about killing a bunch of random people. I also like how a lot of the missions tie together. There's some creativity with the missions. (Ex. Instead of just getting to the helicopter, you have to get the keys first.) Someone said they completed the game in 15 minutes, but it took me a solid hour. The last level was really fun, me and my friend took turns playing it until we beat it. For $0.99 and with the promise of future updates, I would reccomend that you pick this game up!