Invision - Prototyping and collaboration for design teams
Diagramo - Diagramo is an online flowchart software - diagrams (create, edit and share)
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.
Modelio - Modelio is an open source modeling tool supporting natively UML, BPMN and model exchange with XMI.
UXpin - Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
UML Designer - UML Designer provides a set of common diagrams to work with UML 2.5 models.