SIMPLENOTE

From simplenote.com

Available on Mac, iOS, iPadOS

As is often the case with Apple apps, Notes isn’t cross–platform. SimpleNote is, and it does more than Notes too; writing and coding types will love the fact they can use Markdown formatting, and you can also publish to WordPress and share or collaborate with people on other platforms. It’s as much a writing environment as a note–taker, and unlike some rival notes and writing apps it’s free.