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Your product screenshot could be on this portrait 800 x 1280 px mockup. A woman sits low on a futon near the corner of the room. She is surfing the net on her Nexus 7 iPad. The room is comfortable with a wood floor and white wall. The woman is wearing a purple blouse and jean shorts. She is waiting for her friend to arrive, then they will go to the mall and look for your product.
Drag & drop not supported, but you can still upload via this input field: