Facebook Design - Devices - Images and Sketch files of popular devices.
SocialPilot - SocialPilot is an app designed to help businesses and professionals with social media marketing.
Design Cell - Beautiful multipurpose mockups for iOS
Fomo - Fomo turns your site into the online equivalent of a busy store
Clay Mockups - Free set of beautiful device mockups for your designs
Buzzstream - Build Relationships. Build Buzz. Web-based software that helps the world’s best marketers promote their products, services and content.