Can I Run MN in older version of OS like 10.09?
Welcome to the MarginNote Forum.
MarginNote3 requires iOS11.9 or later. But MarginNote2 (pro) can run in iOS10.09. But I recommend you to update your system and use MN3.
MarginNote3 has a comprehensive upgrade compared with MarginNote2 which is featured with OCR, PDF editing, better annotating tools, video excerpts, etc.
By the way,MarginNote3 is constantly being upgraded and optimized, but MarginNote2 won’t add new features temporarily.