While there’s tons of flashlight apps in the Google Play store, a lot of them ask for a high number of and/or odd permissions. While some of the permissions are presumably for advertising, others might be questionable at best.
OI Flashlight is a flashlight app whose only permission it asks for is for the camera, and that’s in order to make use of the camera’s flash. No advertising, etc., and the app’s free.
Features include whether or not to use the camera’s flash instead of the screen backslight, and changing the screen color. However, changing the screen color requires a separate color picker app to download.
The app works as advertised otherwise, and (like most flashlight apps) is easy to use.