Invision - Prototyping and collaboration for design teams
FlowMapp - FlowMapp is a UX planning tool for creating visual sitemaps and user flow.
Zeplin - Collaboration app for UI designers & frontend developers
A1 Sitemap Generator - A1 Sitemap Generator has been in active development and sold since 2005.
Balsamiq - Balsamiq. Rapid, effective and fun wireframing software.
Octopus.do - Build your website structure in real-time and rapidly share it to collaborate with your team or clients. Start prototyping websites or apps instantly.