There's room for a future product to discover everything within a house. Find all the Shelly devices, figure out which bulbs are Hue, discover any small sensors left behind, etc.
Usually its either the relay refusing to switch on or off. Or its able to switch on and off via the app, but not via a light switch that it was happily doing the day before. Or it disappears off the WiFi and refuses to connect no matter how many resets / power cycles are done.
After replacing 10 or so of them, I decided it was easier to rip them all out.