Placeit - Generate realistic product shots in seconds
Mockuuups Studio - Fast and easy way to create product mockups on macOS, Windows and Linux.
AppLaunchpad - Create free beautiful screenshots for App store/Google play
Mediamodifier - Create beautiful designs and product mockups in seconds.
Smartmockups - Create stunning product mockups, easily and online.
mockDrop - Is a webapp for creating free device mockups including your screenshots.