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This flat design keeps it simple with all focus on your mock up. You can put in your image onto a black iPad that will hold 1024 by 768 pixels. The background is a bright blue that will make your app stand out. The iPad casts a short shadow onto the blue for a a little depth. The iPad is in landscape mode and would be great for any sort of app or website mock up.
Drag & drop not supported, but you can still upload via this input field: