Xmind - Xmind is a brainstorming and mind mapping application.
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
MindMeister - Create, share and collaboratively work on mind maps with MindMeister, the leading online mind mapping software. Includes apps for iPhone, iPad and Android.
Sketch - Professional digital design for Mac.
FeatureMap - FeatureMap story mapping, simple and effective realtime collaboration and collective intelligence tool.
Invision - Prototyping and collaboration for design teams