Samsung Galaxy S4 User Manual page 27

Important! If your handset has a touch screen display, please note that
a touch screen responds best to a light touch from the pad
of your finger or a non-metallic stylus. Using excessive
force or a metallic object when pressing on the touch
screen may damage the tempered glass surface and void
the warranty.
Low Battery Indicator
When the battery level is low and only a few minutes of talk time
remain (~15% charge), a warning tone sounds and the
"Battery low" message repeats at regular intervals on the display. In
this condition, your device conserves its remaining battery power, by
dimming the backlight.
When the battery level becomes too low, the device automatically
turns off.
The on-screen battery charge is represented (by default) as a
colored battery icon. You can also choose to display a percentage
value. Having a percentage value on-screen can provide a better
idea of the remaining charge on the battery.
Press
Display
For more information, refer to "Display Settings" on page 343.
and then tap Settings
Display battery percentage.
My device tab
Getting Started 19