How anonymous can a service be that sends messages through a central server and uses your phone's GPS to know where you are at all times? You're only anonymous to each other, but the server in the middle knows all.
When I saw the headline, I thought this used some sort of ad-hoc Wifi network with MAC spoofing and couldn't figure out how they got 1km of range.
The metadata is the problem for true anonymity, not the amount of information that individual users can see, or that the server stores in its database.
When I saw the headline, I thought this used some sort of ad-hoc Wifi network with MAC spoofing and couldn't figure out how they got 1km of range.