Evernote and Linux user here. Their web app is quite good, and their Android and iOS apps are fantastic. Having also messed around with their native app on Windows, I didn't feel like I was missing too much since the whole point is really the content of the notes.

For what it's worth, there are a couple clones of the native app for Linux including Everpad and Nevernote. Haven't tried them because the web app does everything that seems necessary for me.