The case for open source flashlight apps

There is really no need to download flashlight apps off the Google Play Store, because many of them want access to one's contacts and maybe other privileged information. The solution is to get an open-source flashlight app that is much more light-weight, and won't ask for too many permissions.
Initialy written as a reply comment on YouTube.

If your Android phone is relatively basic, and does not have a built-in flashlight, then the F-Droid store of free and open-source (FOSS) software offers many small-sized flashlight apps that do not require access to contacts.

This does require (temporarily) enabling third-party installs, but the open-source flashlight apps' much smaller size removes the requirement for Play Store-based apps that want access to data that they should have no right to have access to.

In some cases, a phone may have a built-in flashlight, but no OS-level functionality to turn it on. This applies to older versions of Android, which I've seen with Android 4.0 ICS (Ice Cream Sandwich), but may as well apply to any Android 4.x version. That's why an app is still required. Some flashlight apps available on F-Droid do require camera access to control the hardware flashlight.

In the F-Droid store app, search using the 'flash' and 'torch' terms, which will match anything that contains these patterns. I've chosen MrWhite, which is only 21 KiB in size.

Depending on version, Samsung smartphones' TouchWiz UI allows adding an "Assistive Light" widget for phones that have a built-in hardware flashlight.

Android-native flashlight functionality is accessible via Google Now in Android 5.0 Lollipop. I don't know, if the function is accessible by other means. Android 6.0 and 7.0 should have the flashlight functionality built-in — check the expanded notification area.