About the battery edge indicator
By default, when you plug in your device, the battery edge indicator appears as a strip of color on the right edge of the
screen. The strip grows and transitions from red to yellow to green as your device charges.
When your device is asleep and charging, the indicator displays the percentage of your current battery power and
estimates how much time is left until the device is fully charged.
To avoid disturbing you, the indicator automatically disappears when the room is dark or when your battery power level
reaches 100%. If your screen is turned on, the indicator automatically disappears after eight seconds. It appears again
when your screen turns off.