I need to be able to take quick, short observations; longer notes with basic formatting (indentation, bullets, underline) and lists of things. I need the longer notes to be accessible and editable across multiple devices.
After trying several notes apps I've settled on the following:
-for short observations that are ephemeral (like a diary), I've ended up using the notes app on an old ipod (great keyboard for one handed use, and it's great for music, has a very long battery life and it's very thin meaning it fits almost unnoticed into any pocket). The other app that I used for a while was somnote (also works across multiple devices).
- for longer notes evernote is perfect. It has sufficient formatting options and works brilliantly across Android, ios (pad and ipod) and Windows pc (somnotes is a contender for this category but somehow evernote seems simpler yet more versatile).
- for lists of things (shopping lists etc) Google keep is ideal.