Enable Power saving mode to prolong battery life. Note: To access, swipe down from the Notification bar > tap Settings icon > under SYSTEM, tap Battery > tap Power saving mode.
Set the Brightness to low or automatic. Note: To access, swipe down from the Notifications bar > tap the Settings icon > under DEVICE, tap Display.
Set the Screen timeout to a shorter duration. Note: To access, swipe down from the Notifications bar > tap the Settings icon > under DEVICE, tap Display > tap Screen timeout.
Turn off Bluetooth,Wi-Fi and NFC when not in use. Note: To access, swipe down from the Notification bar > tap Edit.
Turn of Location services. Note: To access, swipe down from the Notifications bar.
Turn off the Auto-update apps feature in the Play Store. Note: To access, from the home screen, tap Play Store > tap the Menu icon > tap Settings > tap Auto-update apps.
Disable automatic Sync. Note: To access, swipe down from the Notification bar > tap Edit.
If you are traveling and do not have access to mobile or Wi-Fi networks, switch to Airplane mode. Note: To access, press and hold the Power/Lock key.
The maximum talk time for the Samsung Galaxy S4 is 17 hours. The maximum standby time is 15.4 days. Note: For information about charging your battery, search tutorials for ‘Charge battery.'