Everyone I know has a flashlight app on their phone. Most of them are malicious and we don’t even know it. The safest one I know is the “Flashlight Free: No Permissions” from Humberto Tools. I installed that one because it is straight forward, doesn’t get my personal information and you can either have the beam from the camera light or the screen will glow white for a softer light. Here is an article by Wired magazine with the details of the threat.