Mockuper - Instant Mockup Generator
Mockuuups Studio - Fast and easy way to create product mockups on macOS, Windows and Linux.
Mediamodifier - Create beautiful designs and product mockups in seconds.
Placeit - Generate realistic product shots in seconds
uiprint - Printable templates of mockup, wireframes and sketchpads
mockDrop - Is a webapp for creating free device mockups including your screenshots.