Invision - Prototyping and collaboration for design teams
quickMockup - Online tool for creating mockups in the browser.
Marvel - Turn sketches, mockups and designs into web, iPhone, iOS, Android and Apple Watch app prototypes.
UXpin - Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
AppTaster - Share mockups and wireframes with clients on their iPhone or iPad.
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.