Smile has released PDFpen 3 and PDFpen Pro 3 for macOS (10.11 and higher). They’re PDF editing apps that allow you to sync documents between devices for editing via iCloud Drive, Google Drive, and Microsoft OneNote.
Version 3 is made for iOS 11, using the new Files interface for document management. The upgrade also support drag and drop in iOS 11.
PDFpen is available for $74.95. PDFpenPro is $124.95. Demo versions are available at the Smile website (https://smilesoftware.com/PDFpen).