1. On the home screen, swipe down.
2. Select Settings > Battery saving mode.
Now, change the settings as per your requirements.
a) Set power level at which you want power saving mode to turn on automatically, by sliding the toggle left or right.
b) To set those settings which you want to be altered when power saving mode is on , by checking/unchecking respective boxes.
The above information has been taken from the online FAQ/user guide from official BlackBerry website.
Live....and Let Live!
1. Move to the Setting of the phone which can easily be done by swiping down the Home Screen.
2. Slide downwards you can easily find Battery Power Saving Mode.
If you can't find the mode then maybe you are using Older OS of Blackberry. If it so, then go for an update. Update keeps you updated with latest tweaks and always comes up with new features.
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