May 08, 2013, 12:22 PM — Here's how you can use power saving mode on the Samsung Galaxy S4.
1. Swipe down from the notification shade.
2. Tap the icon in the upper right corner to access power saving mode.
Your phone's CPU will be throttled, the background colors will be changed, and the brightness will be lowered to save your battery power.
For more, see the original article at the link below.