title: Is there any point clustering algorithm to collect points into nearby groups?
body: <p>I am writing a iOS photo manage app. </p>
  
  <p>I want to collect photos into groups by their GPS information. Then I can get the mean GPS information of a Group, and give the group a name, for example:Trip to　New York.</p>
  
  <p>Is there any handy algorithm to collect nearby Photos into groups　by GPS information?</p>