This app was mentioned in 13 comments, with an average of 1.23 upvotes
Nimbus Note has a dark theme, and has folders, tags, and rich text features. There are apps for Android, iOS, web, and Windows.
Look at Nimbus Notes as well. https://play.google.com/store/apps/details?id=com.bvblogic.nimbusnote
Nimbus Note has a "share as pdf" option
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And try Nimbus Note