Choosing a background that keeps the screen the subject

The background is the largest area in a mockup and the one most likely to be chosen carelessly. Its only job is to make the device read clearly and to carry the brand. Every unit of visual interest it adds is taken from the interface, which is the thing you are actually selling.

Gradients: subtle, and lit from one direction

A two-stop gradient with a modest range works almost everywhere. Match its direction to your lighting — if the key light comes from the upper left, the background should be brighter there too, or the image will feel subtly incoherent. Avoid gradients that pass through the same value as the device body, which makes the silhouette disappear along part of its edge. If you are exporting JPEG, check for banding in wide flat gradients; a very slight noise overlay fixes it.

Flat colour is underrated

A single well-chosen colour is faster to produce, compresses cleanly, translates perfectly across an eleven-language set, and never fights the interface. It is also what makes a listing feel designed rather than decorated. If you use your brand colour, use it at a value far from your interface's dominant tone so the device separates clearly, and keep the exact same value across all assets including the feature graphic.

Photographic backgrounds: rarely, and only for physical products

A desk, a hand, a coffee shop — these add realism at the cost of noise, and they date fast. They earn their place when the app is about the physical world: a travel app, a fitness app, a tool used on site. Even then, blur the background heavily so the device remains the only sharp thing in frame, and keep the colour temperature consistent with the device's lighting.