Countries using miles per hour as unit of speed

Lately I have continuously improved my latest Android app,
GPS Location Recorder. One feature with the app is to show the speed as you move.

In the beginning I only supported kilometer per hour as unit of speed as most countries use this unit. 

But I also want to support miles per hour as unit of speed. But which countries us miles per hour?
Only two countries according to this Wikipedia page.
Only United Kingdom and United States.