Shared Apple notes are more than enough.
Discussion
ANOSTR
Yes 
Grug brain
Never thought about sharing Apple Notes. Have recently been playing around with Microsoft OneNote and Groups for things though.
They can even be shared with people that don’t use iPhone or Macs
Yes. For a private alternative with cross-platform syncing, you could try standardnotes.com though.
By far my favorite app.
Enlighten me
Shared with other prisoners of Apple. Using the trustee to get cigarettes, swole and toilet wine.