Gold Coins & Building Your Kingdom
Gold coins are used as currency in Super Mario Run. You can use those coins to buy items in the Store and then you can place those items in your Kingdom wherever you like. As you win Rallies and gather Toads, the different colors of Toads are sorted into groups and tallied. As you continue to bring Toads to your Kingdom, you level up, which unlocks special items in the Store and slowly restores your castle to its former glory. You can see what the castle originally looked like at any time by tapping on the castle itself. Once you reach level 20, the castle reaches its maximum expansion. The thing I love about that seemingly annoying paywall at the beginning of Super Mario Run is that it's the only real money you spend on the game. Once you pay the ten, there's no advertising to buy more coins or Rally tickets.