

Tags are metadata in Evernote where in OneNote they are just text added to the note.

Tagging is another part of Evernote that I think is setup very good. Having used both Evernote and OneNote I find Evernote much more valuable and functional. I also find that sharing notes and notebooks is much more convenient, the security setup on note / notebook level is clear and easy to manage. I have not tried to extra text from a pic (OCR-Extracting) because I can search within each of the pics that I add as well as PDF, Word, etc (with Premium).

You can search across notebooks very easily. The design of Evernote allows you to concentrate on the information you are taking. I have tried to switch to OneNote because the company I work for uses Office 365, but I find Evernote much more usable. Evernote lets you search in pictures for text.
