Adding variety to the formula are power-ups that can be collected to improve your score. The Jetpack and Coin Magnet help earn you a ton of coins (the former allows you to launch above the train tracks entirely in a mad-dash to grab coins), while the Sneakers and Multiplier (temporary boosts that increase your running speed or score) barely earn you any additional coins and will likely put you in harm’s way in attempting to collect them. You can also complete a series of missions that reward you with even more coins along the way.
Any of these power-ups, along with a few additional one-time use items like the hoverboard, can be upgraded with the coins you collect while playing. Yes, you can purchase coins if you want, but you earn them at a fairly rapid clip on your own so it’s not necessary to buy anything with real money if you don’t want to.