You can store your downloads in your account when you signup!
A man is holding up an iPhone 6 mockup. He is standing in his home. In the background there are festive lights decorating his window. He is holding the iPhone 6 in one hand and using the other to press a button. The iPhone 6 mockup holds an image of 750×1334. This is the perfect place to show off your app.
Drag & drop not supported, but you can still upload via this input field: