title: how to use sync api to upload file to dropbox android
body: <p>I am a new android developer, I want to write a program to upload a specify file from my mobile to Dropbox whenever it is updated in local.</p>
  
  <p>Should I use Sync API or Core API? Or both can archieve my aim?</p>
  
  <p>For using SYNC api, how can i locate the local file location?</p>
  
  <p>Thanks.</p>