Placeit - Generate realistic product shots in seconds
Mediamodifier - Create beautiful designs and product mockups in seconds.
PicApp - PicApp was created by the awesome team from AppDemoStore.com to help you show your app to the world.
Magic Mockups - Place your product screenshot in real-life environment.Free iMac and iPad mockups ... read more.
AppScreens - Screenshot creator for the Apple App and Google Play Store. Generate designer quality, pixel perfect screenshots for your iOS and Android apps at the same time
mockDrop - Is a webapp for creating free device mockups including your screenshots.