If you're not getting a response from either drag and drop or from select button, then Javascript is not enabled or being blocked? Or possibly using an unsupported mobile browser?
This web app is not intended for those with image hosting accounts, which does have the distinct advantage of allowing one to manage photos from one central site. But you also don't have to determine whether your photo is sized correctly for the forums max 640x480 or 480x640, and thus have to resort to using switches to adjust the display size. Which does nothing to change file size itself and can waste unnecessary data bandwidth for those of us on mobile connections.
Not to mention that IMGUR servers are very fast, as it take me about 6-7 secs using the web app to upload a typical photo, resize a smaller copy at 640x480, and provide a forum specific copy & space link. And you can always bookmark the delete link should you ever want it permanently removed from the server.
