When I open an .apk file, a permission screen pops up (as expected). If there’s many of them, I can scroll the page just fine. At the bottom, Cancel and Install buttons are visible. Tapping on Cancel closes the window (again as expected) however tapping on Install does absolutely nothing. It appears as if that part of the screen was non-functional except that it works fine outside of the permission screen.
I have unknown sources and privacy impact enabled.
I have tried rebooting.
I have tried installing apps from F-Droid as well as by directly opening .apk files in Ghost Commander.
Maybe you have some app running that creates an overlay and “blocks” that specific part of the screen?
For example, for me this happens when I’ve got the Tap'n'Turn app running. I have to disable the Turn-Feature in the app and then actively close the app, so that part of the screen gets “unblocked”.
The most common examples of screen overlay apps (that will indeed block the install button) are apps like twilight and F.lux, which people use to reduce blue light from the screen.
Good point - vaguely remember someone mentioning that it also caused problems with the install button, but I’m probably just remembering that wrong!
On a side note, this makes F.Lux more interesting, because the approach of adding other colours seems limited when you actually want to remove a specific colour…
Downside is that f.lux is not open source, and it doesn’t work on Android versions below Lollipop. I tried to get in contact with them some days ago and they never responded…
PS.: I’m using Red Moon, which also uses an overlay. This overlay disables itself when you do an app installation, but not when an app asks for superuser permission.
Yes, this is a bit weird but I can understand it from a security perspective.
If there’s any overlay Android won’t allow you to install apps from unknown sources - because an overlay might trick you into doing something you don’t want to.
(It would still be nice, if there would be a warning that this is the reason.)
The setting has a scary warning about shortening battery life, so in the end I chose not to enable it. I hope I’ll remember next time to pause Red Moon when I try to install .apks.