An easy option. It’s everywhere in Cambodia. Tourists love them. But you need to negotiate with the drivers the price before you hop on and they usually charge quite a high price. As a tourist, you need to be prepared to be ripped off. You probably don’t mind because for you, it could just be USD1 or USD2 difference but I always discourage tourists to do that because it will encourage the tuk tuk drivers to continue to rip off the tourists.
I used tuk tuk a few times only in my seven and a half months there. I used PassApp most of the time.
Note: make sure you wear a mask. It’s very dusty in Cambodia.