Performance on Google Maps and SqlLite

In my application I have a Activity with google map and a GPS to get my location as I am walking. The application works well, as I'm walking the map will show what is close to min (markers) my problem: Knowing that SqlLite is not supported math functions for distance calculation points, must seek all entry and make the calculation by a method in my code, keeping in memory, however, lose performance to get all the bank's record and analyze each. Any suggestions of what I can do to improve application performance, considering a bank with 60,000 coordinate registration