I switched to Bear after having significant sync problems with apple notes (it was fine in iOS 10 but never ever worked properly in iOS 11). It was always OK on my Mac.
From various Apple support forum requests it seems that a lot of people were having similar - but also a number were totally unaffected.
My biggest gripe with Apple Notes is if I throw some snippet of code in there it mutates the quotes to "smart quotes" and thus the code produces syntax errors if I try and use it again :(
Btw you can disable smart quotes system wide on macOS, it's in keyboard settings.
Re:Ask HN: Favorite note-taking software?
by mark_l_watson on Sunday July 15, 2018 @09:57AM
(#17535249)
I started to switch to Apple Notes a year ago, loved it, then discovered there is no good way to export all notes as text for backup.
Any suggestions?
For anything more technical I use Quiver which supports MarkDown, code with pretty printing, LaTex and diagram markup, but it doesn't have an iPad editor (just reader).