I’ve never found mind-mapping to be particularly useful, but I’ve started to use them here and there since getting the MindNode iPad App. Something about combining this type of application and the large touch screen of the iPad makes sense. There is also an iPhone version but I don’t know if it will work on the small screen as well.
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Funny, I just started playing around with mind mapping as well. I started with iThoughtsHD but have moved to MindNode on the iPad because there is a corresponding OS X version. I don’t think the iPhone is the right platform for this sort of software, but I guess that if that’s all you have it’s better than nothing.
btw- If you find yourself using this application more I’d like to see a MacMost video about your usage.