title: Long-running upload techniques
body: <p>I have an application that will be uploading large files in the background on iOS (e.g. DropBox style).  What are some different techniques to keep the uploads moving?  So far I have:</p>
  
  <ol>
  <li>Receive callbacks from the background networking service (NSURLSession), and resume a limited number of times (since the callbacks decrease in frequency)</li>
  <li>Resume uploads when the app opens</li>
  <li>Resume uploads when the location changes (which seems to be what DropBox does)</li>
  </ol>
  
  <p>Are there any other techniques to ensure that background uploads complete?</p>