I'm using Google docs. With sufficient tabs and links between docs and spreadsheets works great.  

 Freeform is kinda „free“. As long as you are in the  system. 

 pen & paper 

 I knew someone was going to say that. 

 Check Obsidian. It offers both markdown notes and canvases to draw. Everything is on your laptop, simple syntax, good search and other stuff. 

 On foot (?) => Freeplane

Civic (?) => SimpleMind

Ferrari (?) => TheBrain 

 Obsidian 

 #Obsidian 

 Silencio...  you walk and map out in real time .

I have a refferal if you would like to join ... I use this app as my walking meditation sessions.

https://m.primal.net/LjtU.png
https://m.primal.net/LjtY.png
 

 send it