For a couple of months now I get this weird overlay of other apps on my screen. It happens consistently and the app that's overlaying is one I just used, I've restarted my phone multiple times, the overlay doesn't appear on screenshots
Welcome to Android Central! Which phone? Can you show us a screenshot? http://forums.androidcentral.com/ge...ide-how-post-screenshots-android-central.html
the overlay doesn't appear on screenshots
Derp, I don't know how I missed that in your OP -- sorry!:-\
Instead, can you take a picture of the screen with another device and post that? The actual image might jog the memory of other members, if they've experienced the same thing.
You might also want to see if any currently installed apps have a screen overlay, and turn it off temporarily: https://www.howtogeek.com/271519/how-to-fix-the-screen-overlay-detected-error-on-android/
Welcome to the forums. The overlay you get, is it always like a shadow of the previous app you used? If so, that sounds like screen retention. I remember reading similar reports with the G4. How high is your brightness level (settings - display)?