F.E.
F.E. reviewedKeep ItRobust Evernote alternative.
 RecommendedPros: 

Clean, great tagging/filtering, supports all file types, selective folder/list sync

Cons: 

(Initial) syncing can be sluggish

Great app, cross between "Everything drawer" (Devonthink) and note taking (Evernote). Cheap compared to both, well designed. I especially like

1. the tag-based filtering options,

2. that it uses the (macOS) file system (you can browse all lists in the Finder, tags are written to the files), and

3. that i can selectively sync (download) files and folders on iOS.

Also: Very fast response to my support questions.

F.E. has used this product for one month.