> see the location of every phone passing your public key encrypted bits back My understanding is that (in this scheme) all location data is encrypted by keys

> see the location of every phone passing your public key encrypted bits back My understanding is that (in this scheme) all location data is encrypted by keys unknown to apple, i.e. the reporter uses the lost device’s public key to encrypt its location and transmits it together with the hash of the key. However, apple seems to be able to infer proximity of two reporters, as described here https://news.ycombinator.com/item?id=20135995 https://news.ycombinator.com/item?id=20135995 Edit: except if the Lost device is controlled by Apple, then they can decrypt the location of the reporting device.