First, you need to find out the exact apps which are just sucking away the battery juice the most. Since iOS 8 has a built-in feature offering a percentage breakdown of the biggest energy draws on the smart phone, we can use that tool to identify such apps so as to close or even delete them. It is very easy to do so. Just go to Settings>>General>>Background App Refresh.
You must be familiar with background App refresh. The iOS 7 also has such software. When we set the app on, it will run in the background when we refreshes the content. We can choose to turn such function off by visiting Settings>>General>>Accessibility and then set Reduce Motion to "On." It will drain the battery life as well if we let it on.
When you are out, finding the ways with location tracking apps, you will find the battery life just decrease easily. The constant monitoring will just eat away battery life. So try to go to Settings > Privacy > Location Services) and turn off Location Services. Besides, if we constantly search for Wi-Fi, the battery also dwindles easily. If we fail to find trusted network available, just stop searching it or we can turn off the Wi-Fi so as to save battery life.
One of the new features from iOS 8 is the convenient widget which we can access from the Notification Center. We can pull down from the top of our phone screen to customize information such as sports news, weather updates, etc. Of course, such widget also drain the battery if it pulls new data too frequently. Try to disable those widgets that we do not have to use often. It's very easy to do so. Just "Edit" menu at the bottom of the Today screen.
Turn down the auto brightness mode if we do not want to see our battery life is automatically reducing fast. Though the auto brightness can keep the phone screen much brighter, it is not necessary if we are out in the bright sun.
Try these ways out to see whether they really can prolong the battery life for your smart phone.