uleFone Armor Mini 5 Achievement Unlocked: Sideloading Apps

So this works fine once you reassure Android it's okay to install apps from unknown sources. 😁

In this case, both APK files were available directly from VideoLAN and Opera. No need to use an app store or APKMirror. Open the file, acknowledge the warnings, and you're good.

The only irony is that I used my Armor Mini 20 to download the APK files and transfer them to the Mini 5 via (slow) Bluetooth.

VLC solved the problem with the phone's built-in media player unable to play anything else besides MP3 and MP4 files, and only if they're properly encoded. I've confirmed VLC can play almost anything on this phone including AVI and MKV files.