Hi there!
With the recent release of freeform in the latest update delivered to iPad, Mac and iPhone, I think we have in our hand a great visual thinking tool. We have an unlimited canvas and easy to use tools to doodle, draw, sketch and visualize anything we are trying to learn and organize.
The power of doodling to enhance knowledge recall and understanding have been shown: https://medicalxpress.com/news/2011-08-doodling-science.html
Personally, using this tool along with others like Curio will create interesting ways to learn new things. I just ordered some books related to visual thinking. I tried to use the app “Concepts” due to the infinite canvas, but it had too many tools and I felt lost attempting to use it. Freeform, on the other hand, is really intuitive and simple to use.
What about you? What do you think?