Flappy Bird might just be the most viral app of all time. The arcade game's concept was simple: Fly through a series of Mario-esque pipes and avoid touching them. Unfortunately, Flappy Bird was so addicting that its creator pulled the app from the App Store, but if you grabbed the app beforehand, you can still play.
The frustrating fun is back with its sequel, Swing Copters, which is a physics-based flying game that asks you to fly skywards while dodging the swing the hammers. Curiously enough, its tricky physics might make Swing Copters even harder than Flappy Birds, even though you just navigate with a tap.
Price: Free (iOS, Android)