Pre-convert contacts address into geo locations.
Those geo locations are saved on the server.
When you ask for nearby contacts, the app will retrieve those near by contacts from the server.
Only address id and geo locations are saved on the server and private information is not saved. (i.e. names and address are not saved on the server)
If you feel you need more functions, please send a request from the app.
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For those who are found of this app and if you are native in English, Im very much happy if you can rewrite this description.