Evernote is my go-to app for mobile notes. I use it for writing down ideas when I'm on the go. I can easily pull up the desktop or web interface at home, and revise or add on to my notes. Some of the advanced functions are not as easy to use or learn as with OneNote. I've had a few hiccups with syncing, which caused me to dock some points, but their help staff was very friendly and quick to reply. However, as with all cloud based apps, the ramifications of a bad sync or data failure can be huge. So, while I still highly recommend Evernote, I would also recommend backing up to your email, Dropbox/Box.net/etc, or to physical media (hdd, cd/dvd, usb drive) to ensure you never lose anything.