Maybe it was originally viewed through a performance perspective only, with the idea that all of the data crunching should happen on the front end to provide a faster server response?
Just rounding a location integer can be done in less than 10 assembly instructions. May be the time spent on that can well be compensated by transferring less data (orginally we transfer a float now we only transfer an integer).
Anyway, the point is processing this one sensetive information on server side really take little time. Maybe only several nanoseconds? The network latency is the botttleneck, not the proceesing of several bits of data.
This is something the phone of each user itself could do. All that is necessary is for the app to generate a random offset for the latitude and another one for the longitude at startup then report their location + constant offset instead of their actual location to Tinder.
Now the worst thing that will happen is someone triangulates a point say, 1/4 mile away from you.
