I worked on a team of 4 to develop a novel application for AR. We went through a long process of needfinding and eventually decided to create an AR game to motivate people to donate to charity.
We defined a category of games we call Penny Games. There can be many different penny games, but they rely on a common core mechanic: the game pieces are pennies, pulled from a user's bank account, and when the game ends, the pennies used are donated to a charity of the player's (or game designer's) choice.
We brainstormed several possible games and settled on one called Coins for Climate. The game is about protecting a tree while it grows by shooting coins at pollution clouds and bulldozers trying to harm it.