Meanwhile, with Google's upcoming restrictions on 'sideloading' (I.E. installing apps that haven't registered with Google, including paying them a fee and providing your government ID: see more at https://keepandroidopen.org/), soon the only way for users running Android to install apps that Big Brother Google hasn't approved will be... enabling Developer Mode.
Enabling Developer Mode of course requires a 24-hour waiting period, so you can't just turn it off real quick to use this app and then back on, either. (EDIT: Apparently the 24-hour waiting period only applies to the first time enabling developer mode. The rest of my concerns stand, though.)
If apps refusing to run in developer mode is or becomes a widespread thing...well, it ain't good. And making it so that important publicly funded apps can't run in developer mode would be an easy thing for Google to lobby for...