First and foremost, the first thing we can do is extend standby time and save your battery power. You can obtain ROOT access through KingRoot.

PURIFY works only with ROOT access so if your device is not rooted, you must obtain it before using PURIFY. She can help you to save battery power, improve device standby time, increase speed and return your device to it's pure state. PURIFY is an optimized tool for your Android OS. Meanwhile, unroot operation also can be done easily by just click the button in the menu of KingRoot. What’s more, KingRoot(app) will not trip Samsung KNOX and have ability to close Sony_RIC perfectly. So, it’s necessary to keep net connection during root process. The most suitable Root strategy will be deployed from cloud to your device according to your ROM information. Working of KingRoot based on system exploit. It can work on almost all device from Android 2.x – 5.0. KingRoot is a root tool for 'lazy people' who just want to get root access but don't want to flash any third party Recovery into their lovely device. This release does not have a Play Store Description, so we grabbed one from version 4.8.1:

King root apk 4.4.2