If I recall, there was a dating app that showed you profiles of people you'd crossed paths with that day - so, basically a conventional dating app with a novel algorithm for choosing which profiles to show you. If I'm understanding you correctly, what you're suggesting has minimal profiles; it just notifies you that a given person is nearby and that you might want to talk to them. I can see two problems with this. Th…
how about adding a matching on/off switch? for example you go to an event and turn it on and thus make urself "matchable" so it would simply make rejection disapear the difference between this and the pear ring is the simplicity of an app that you can download and start using instead of purchasing an extra item that you have to wear
If you think about how meeting new people currently works, there's a bit of sizing people up to decide what sort of chances you have or whether they're a creep before you decide whether to go and talk to them - I think that's the crucial aspect your idea is missing.