If you aren’t familiar already dev.to is a pretty neat developer community site. Occasionally they have a challenge that members can try. There is so much content on the site, but this one particular article caught my eye.
In this case the problem was solved as a little game that uses API, but real world hardware too – it’s a cool idea.
The topic might not be of interest to you, but the site is pretty cool – take a look!
https://dev.to/jamesrmoro/castle-of-keys-api-first-access-control-in-a-physical-digital-game-2f70
The author (James Moro) also has a nice YouTube video explaining it.