iOS: If you have a history of waking up, turning off your alarm, and then falling back to sleep, Game Up Alarm Clock might help. Instead of just waking up to music or a buzzer, you have to play simple games like tic-tac-toe to get the alarm to turn off.
Game Up Alarm Clock does two things to make sure you actually get out of bed. First, it has no snooze button, which eliminates that terrible temptation. Second, it gets your brain going immediately so you don't just do something by muscle memory and go back to sleep. It's nothing too challenging -- the games are largely tic-tac-toe against the computer, or a puzzle game where you have to pull a selected lever. Once you win the game, the alarm turns off.
Beyond that, Game Up Alarm Clock has all of the other features you would expect in an alarm clock. It will show you the weather forecast, it lets you choose a song from your playlist to be your wake up alarm, and it's gesture based for easy controls. The app is free in the iTunes App Store.