104D-Link DIR-850L User Manual
Section 4 - SharePort
Tap on a le to start the document viewer. In the viewer:
•  Tap the screen to reveal the zoom in/out buttons.
•  Drag the screen up or down to scroll between pages.
•  Tap   to perform actions like Find, Zoom, Reading View, Go 
to Page, and Bookmarks.*
 *Note: Available actions may dier depending on your Android OS.