well, only so many devices one can control through IoT. (home)
but if to combine with different environments,
water(ocean, lakes), security cameras, space (one day)....
tunnels, pipelines, bridges, forest/nature, labs, etc.
or generally to interact with Tesla bot.......
etc. i'm sure there are more usage....
3D printers... desktop manufacturing tools.... etc...
automatic bird feeder....
car location/battery check....
tracking devices....