DEVONthink To Go is also deeply integrated into the Files app so that your databases appear like a local file system to other apps.
Add links to your documents to all apps that take web addresses, e.g. OmniFocus or Apple Notes, or export your documents in their original file formats to the Files app and all other apps that support it.
Edit texts, Markdown files, or rich text documents, or open files in other apps if the built-in editing capabilities are not sufficient.
Use DEVONthink To Go’s Shortcuts actions to integrate it with other apps.
DEVONthink To Go lets you take your important documents with you on your iPad, iPhone, or iPod Touch.
Save files, via Files and iOS’ file provider mechanism, directly to DEVONthink To Go.
Browse PDFs, notes, images, bookmarks, and just about any file type, neatly organized into databases and groups.
Like DEVONthink for Mac, DEVONthink To Go offers many ways to organize your document collection.
Set up workflows with all the steps from creating new documents to reorganizing your databases along rules you set up.
Predefined smart groups show you, e.g., all your flagged or unread documents.
Sort documents into groups, add them to more than one group at a time without duplicating them, or add tags.
If you're serious about working on iOS, DEVONthink To Go is your document repository when you're not at your Mac.
Synchronize your databases securely and privately over the local network or through a cloud service of your choice.
Read web pages as if they were local documents.