OneNote Mobile may be the best kept secret of Windows Phone 7 (WP7). By default OneNote syncs any notes you create on the phone with a notebook called Personal (Web) on your Windows Live SkyDrive. This is great. It provides a cloud-based copy of all your notes, which is editable from your PC using Office 2010, or in the browser using Office Web Apps. It really is OneNote everywhere.
But what if you want to use multiple notebooks? Or what if you want to share a notebook with another Windows Phone user? This is where OneNote really gets killer, but unfortunately it’s not readily apparent. By default OneNote only uses a single notebook, and that can only be sharedby editing permissions from the web, not on the phone. In addition, individual tabs don’t seem to be shareable, only the notebook.