UI Garage - Specific mobile and web design patterns for your inspiration
Invision - Prototyping and collaboration for design teams
Muzli - UI/UX and Design Inspiration Chrome Extension
Marvel - Turn sketches, mockups and designs into web, iPhone, iOS, Android and Apple Watch app prototypes.
Design Hunt - Curated design inspiration for everyone
Axure RP - The prototyping and specification software used by 87% of the Fortune 100. Beyond mockups, design interactive prototypes for business solutions, websites, and applications.