When you pass a level on your first try, you are rewarded with a Golden Pin for the level, visible on the map screen.
If you complete 35 Golden Pins you'll even see a lovely Golden Crown, perched on the level icon! How regal!
These Golden Pins are the rewards for passing a level on your first attempt and give you unique bragging rights when comparing them against your fellow friends and family who also play.
So open your maps and compare the golden glory between your games!