There’s no official mobile app. But the website works pretty well on mobile.

I have added free hotlinking for image files up to 1 MB

Hmm, that’s tough. I may have to loosen the rules somewhat. Currently hotlink protection kicks in when the file has 5 times more downloads than views. Maybe I can remove the constraint for files below 10 MB.

The protection was originally put in place to prevent the spread of viruses though, not just to get people to pay. Viruses often spread by uploading themselves to file hosts and downloading themselves on other vulnerable hosts. I added the hotlink protection after a faulty virus downloaded itself 10 million times, causing pixeldrain to get overloaded.