Alcatel Idol 4 Quick Start Manual page 10

For your convenience, your phone features a unique
Reversible UI, which ensures functionality, including normal
call, even the phone is held in reverse (upside-down)
position.
3.2.1 Reversible call functionality
Your phone features a unique Reversible UI, which ensures complete
functionality. When this feature is enabled through the Settings\
Display\Reversible rotate menu, it allows normal calls to be made
or received even when the phone is held upside down. The reversed
UI will appear upright and normal, even if the phone is upside down.
When in the reversed position, the phone UI will appear upright and
normal. The phone will function normally in all respects as it relates
to interacting with the display, except that the power and volume
keys will be on the opposite sides of their normal position. Also, take
care to remember that the camera lenses (front and back) will be
toward the lower edge of the device when in the reversed orientation.
Please note that while a call is connected (user has selected Answer
or Send), the UI will be fixed for the duration of the call. To disable
the Reversible feature, go to the Settings\Display setting menu and
disable Reversible rotate.
Always make a visual inspection of the proper UI orientation when
making or receiving a call to avoid placing the incorrect end of the
phone to your ear. During an active call, if the phone must be taken
away from your ear (eg, switching hands or to the other ear) please
use caution not to use the phone in an orientation opposite that of
which was used to originally make or answer the call. Doing so could
cause unwanted, albeit brief, exposure to additional RF to the user.
Only the active receiver (speaker) serving as the «top» of the device
will function during the call so holding the device inadvertently in the
opposite orientation will result in not being able to hear the other
caller from the receiver against the ear. The user just needs to rotate
the device back to the correct position to continue the call. Use of
third-party auto-answer type features is also not recommended.
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