Huh. Used to be an Apple Developer program subscription was required to sign anything running on a physical device. Seems to no longer be the case? Or does the Configuration Profile installation allow running code signed with some self-signed certificate?

A free developer account has been able to do this for a long time now. It’s just meant for hobby development, so it does come with the limitation the install only works for a short while, this program attempts to work around that by reinstalling the app periodically.

Also, limited number of applications you can have at any one time.