I developed it using the Marmalade SDK which targets iOS, Android and the Playbook. There was a promotion where they gave away developer licenses for six months so you could develop apps and if you submitted one get (another) Playbook. The Marmalade tools are really good, making building, deploying and debugging pretty smooth. The SDK has all sorts of libraries which came out of Ideaworks3D Game studios game development.
The game is based upon one of the samples, where a square on the screen moves towards your finger when you tap or press on the screen. Two of my sons, with the Playbook between them, started trying to get the square to move towards them, and the idea was born. My wife gave it the name - Tap Tug of War - and all three sons playtested it. To stop you just holding your finger down I made it so that if you pressed for two long the square, which became a fuzzy blob for the final game, would move away from you. I put a state machine around the game play for the splash screen, game over and restart screens, created some graphics and the game was done.