4K HD Wallpaper: Planet and its Satellite
Tobias Roetsch is one of the most talented graphic designers featured in gallery. Here's one of his image artworks that can be downloaded free for personal use from his courtesy and use as desktop background and homescreen phone.
Widescreen Desktop / Macbook (Retina): 2880x1800 (fits on: 2560x1600, 1920x1200, 1440x900)
Samsung Galaxy Tab & iPad: 2048x1536 (compatible with almost all tablets)
HTC, Samsung Galaxy & iPhone: 1080x1920 (compatible with many smartphones)