You can store your downloads in your account when you signup!
Your product screenshot will look good in this white iPad mini. This mockup is a subtlety lit desk of a student. But it is also a wooden desk, outdoors. Look, it is now a modern music studio. Swap your backgrounds on this stage! The iPad mockup stage is at portrait orientation and 768 x 1024 px.
Drag & drop not supported, but you can still upload via this input field: