Keys (which look like in the game) are utilities that were introduced in . They are the secondary currency in the game. Most importantly, keys are used to revive your character 1 key, and the cost doubles over time. Keys are also used to unlock special outfits for many characters. There are lots of ways to obtain Keys. For example, they can be found while running, opening a Mystery Box, or from the Weekly Hunt or Season Hunt. You can also buy different amounts of keys from the Shop, though it costs real money. As for the appearance of the key, it is light blue with a white outline, and has a star in the middle of the handle. It is the same star that is on the Coins.
You are given a limited amount of time to decide if you want to revive after a crash.
You can skip this by tapping outside the box when the timer has reached approximately 5/8.
After , your limited to 12 revives only with keys.
The key, the Headstart, the Jetpack and the Hoverboard are the only things in the game that can prevent you from losing, with the exception of the Super Sneakers and Power Jumper, which might both save you and cause you to lose.
In the edition, the Holiday Video was added, allowing the player to receive 2 keys once he/she watches the whole video. But after that edition, it was replaced with the Daily Video, but with the same function.
They are quite a rare item to be found during a run, even rarer than a Weekly Hunt token.
This fact makes the mission "Collect 2 (or 3) keys in one run" extremely hard.
In and the next updates, the video to earn keys it's to earn 3 keys, not 2.