Rewards, once created, can be assigned to achievements. Upon earning an achievement, you can then distribute these rewards to the player. They can be anything you like. You might want to award a certain number of points to a custom leaderboard. You might want to fire off an order to Amazon for a gift card. You might send an email to someone in HR to hand-deliver a weekend getaway package. The possibilities are endless.
Rewards have the following properties:
Rewards can be anything you like, but it's your responsibility to to distribute the reward to the player.