I remember Nothing tech did something similar-ish not too long ago, but I can't find their announcement of it. But then I stumbled upon a video talking about privacy concerns[0]. What's the difference between what they did and what Beeper is doing? Sounds cool though, impressive work! (also, "hacker"-news needs to be more embracing of their name lol)
[0] https://www.youtube.com/watch?v=fMdj8RyMb64