problem

I was building a mobile game, coffeedash, and found that when I played my game on an actual mobile device, my character moved a lot slower than it did when I ran the Unity game on my computer.

solution

The problem was that I was moving my object in the Update function. The Unity Update function is called once per frame and you can imagine that the frame rate of a mobile device is likely a lot lower than the frame rate of, say, a gaming computer.

To fix this, you can use the FixedUpdate function which gets called 50 times / second regardless of what device you're playing on.