SanDisk iXpand User Manual page 27

2. Choose to view files that exist on the iXpand Drive or on the iPhone or iPad
from the slider bar at the top of the screen
When "iXpand" is selected, only those files contained on the drive will be
shown. When "iPhone or iPad Storage" is selected, all files on the phone and
the iXpand Drive are shown. Files also copied from other apps when the
drive is not attached will appear here.
Only Photos and Videos will be copied to your Camera roll on the iPhone or iPad.
Other file types copied to App Storage are only accessible using the iXpand Drive app.
You can select the files stored in the App by moving the slider at the top of the
screen between iXpand and iPhone or iPad.