D-Link AC3200 Ultra User Manual page 147

Section 5 - Applications
Tap on a file to start the document viewer. In the viewer:
Tap the screen to bring up zoom in/out buttons.
Drag the screen up or down to scroll between pages.
Tap to perform File, Find, Zoom, Reading View, Go To Page, and
Bookmarks actions.
Note: Available actions may differ depending on your Android OS.
D-Link DIR-890L User Manual 142