Subway Surfers is a great example of an endless running game.
You take control of Jake, who rides the subways and tries to get away from the Inspector and his dog. In this endless running game, you have to avoid trains, trams, barriers, and more to get as far as you can. In Subway Surfers, you need to collect coins to get power-ups and special gear that will help you go further every time. Coins can also be used to get access to different figures and boards. With your keys, you can change how the characters look and add special skills to your hoverboards. Don't forget to do the awards, since they give you keys.
Have fun and good luck!