title: iOS, How to know whether a photo is a screenshot taken by user? How to delete photos in Photos?
body: <p>In AppStore(China), an App called Tencent Mobile Manager released a series of functions related to photos, including detecting whether a photo is a screenshot taken by user, deleting photos.</p>
  
  <p>I got screenshots of this app to demonstrate my question here (I added English texts myself for you since the app only shows Chinese):</p>
  
  <p><a href="http://i.stack.imgur.com/IEC5I.jpg" rel="noreferrer">This app knows what photos are screenshots and what not</a></p>
  
  <p>When you tap Delete Button at the bottom, it shows:</p>
  
  <p><a href="http://i.stack.imgur.com/YpBfc.jpg" rel="noreferrer">Asking permission from user to delete photos</a></p>
  
  <p>As far as I know, Photo APIs (AssetsLibrary, PHPhotoLibrary) in iOS don't give an absolute path of a photo, and iOS SandBox doesn't allow apps to delete user's assets as well, which makes deleting users photos almost impossible. All photos saved in iOS device follows the same naming system: "IMG_001.jpg", which makes it impossible to detect whether a photo is a screenshot from their names.</p>
  
  <p>But apparently, this app implemented both functions. Does anyone have any ideas about this? </p>
  
  <p>Thanks! </p>