It's limited in time and number of apps, so not really
Gotta pay $100 a year for developer program.
Those apps are deactivated after 7 days unless you pay for an Apple Developer subscription. There's the non-EU version of the AltStore which attempts to circumvent this restriction, but it's a dirty hack and I expect Apple to patch it out eventually.
It doesn't circumvent anything, it just re-signs the apps so they continue working.
This. It's just one more annoying weekly chore to keep in mind, as the automatic backround refresh, in typical iOS fashion, only works when it feels like it. And doesn't work at all if you use energy saving mode.