Mediamodifier - Create beautiful designs and product mockups in seconds.
Anima App - Design, get feedback, convert to code, publish, iterate.
Mockuuups Studio - Fast and easy way to create product mockups on macOS, Windows and Linux.
Sketch Repo - Collection of resources for anyone who uses Sketch
Placeit - Generate realistic product shots in seconds
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.