You can also auto backup your selected notebooks into Dropbox without any manual effort.
Here is how to set this up -
1.Tap on the 'Gear' icon on the main shelf of the app
2.Choose the 'Auto Backup' option in this drop down menu
3.It will show the list of notebooks that are on your shelf. You just have to tap on the notebooks to select them for backing up
4.You will see a blue check mark beside the notebooks that have been selected. When the backup is complete, you will notice in your Dropbox account that all these notebooks will get saved under the 'Noteshelf Backup’ folder for easier identification.
5.Now, in order to restore any notebook in future, you can do so by importing that backed up notebook from Dropbox...just the same way you import new PDF's by selecting the plus icon on the main shelf>>Dropbox>>Noteshelf backups>>and select the backed up file that you want to restore into the app again.