What are some alternatives?
When comparing Ranktab and MindManager, you can also consider the following products
IdeaScale - IdeaScale is the leading innovation management software platform for the enterprise, government, and education.
XMind - XMind is a brainstorming and mind mapping application.
Viima - Viima's mission is to allow companies to build what their customer wants, or in turn to fail faster with minimal wasted effort
MindMeister - Create, share and collaboratively work on mind maps with MindMeister, the leading online mind mapping software. Includes apps for iPhone, iPad and Android.
Crowdicity - Idea management software for smart organizations.
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.