Samsung SPH-D710ZKASPR - Manual (Page 25)

Device Basics 23
Rotate
For most screens, you can automatically change the screen orientation from portrait to
landscape by turning the device sideways. When entering text, you can turn the device
sideways to bring up a bigger keyboard. See
Touchscreen Navigation for more details.
Note: The Auto-rotate check box needs to be selected for the screen orientation to
automatically change. To make this selection, press > > and tap
Display > Auto-rotate screen. See Auto-rotate Screen for more information.