Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Whimsical Wireframes - Lightning fast wireframing with real-time collaboration.
Sketch - Professional digital design for Mac.
Balsamiq Cloud - Fast, approachable, collaborative wireframing
Invision - Prototyping and collaboration for design teams
Justinmind - Define awesome experiences through wireframes & prototypes.