Run 3 is The Best Endless Running Game That You Should Try
Run from Left to Right, from Right to Left. This is the best endless running game I've played. You get started on a very light note: You just have to keep running and cross the 3D obstacles.
Fun Part: You can run 360 degrees! The wall on the sides is not a wall per se. You just make a move to your right, and the character shifts to that track!
Then it gets difficult, you now have skates and the tiles where you run start getting shorter, and you get tiles which will break when you run onto them.
I love this game so much. I've been playing it pretty much every time I can. Seriously if you have some free time and nothing else really to do give the game a shot. It's pretty simple but I love the little interactions between the characters!