Introduction
Keep it Simple is an in-game achievement in Run 3.
Suggested Characters: 
Note: Any character can do this achievement but the Runner and the Skater is recommended because you may only have the Runner and the Skater.
Gameplay
Any character can be used to beat this level but at the time you get to Level 17, you may only have the Skater and the Runner.
As the Runner just jump on the crumbling tiles and hold jump and turn right to get back to a normal tile. Just do this repeatedly and you will earn the achievement.
For the Skater this achievement is a lot harder but possible. You need to just do a slight touch to a crumbling tile and jump back to a normal tile. You need to be careful or you will pass a crumbling tile platform and have to restart.
Trivia
The name of this achievement may be a reference to the KISS principle (Keep it simple, stupid.)