Mindomo is an online collaborative mind mapping, concept mapping and outlining software for visualizing and organizing information. The free version has a three mind map limit, and disables premium features like audio/video upload, PDF, PowerPoint and Excel download, password protection.
Mindomo's registered users can create and collaborate real-time on mind maps, while unregistered users can view the maps shared with them. Additionally, the software provides its users with ways to create presentations and mind map assignments
Sign up for an account to start creating, https://www.mindomo.com.