Am I misunderstanding, is this not that? My understanding is the this will allow you to find devices other than your phone--tablets, earbuds, etc--by triangulating the location using not just your own phone but all Android phones local enough to detect the device being sought.
Yep, but as Google's network (which would be the most comprehensive) is not yet ready, I'm using the next best thing: both Samsung and Apple's - combined.
Note: I don't live in a country where Tiled is sold or used too often, so they're a no-go.
IMO Tile is fine because usually you forget where something is because you left it there, and so your phone will tell you where you left it, you really only need a network if the thing moves after you left it somewhere.