I'm on Andrid, I use a small file manager called MK Explorer [0]

Flow is, open the app, go to bookmarks->notes (this is a shortcut I set up), choose a folder (I have a bunch for different things), then menu button->new file, enter a title, and use the file explorer's own text editor. It's not as quick as opening Google Keep and tapping plus, but at least I know I can trust it.

[0] https://play.google.com/store/apps/details?id=pl.mkexplorer....