At this juncture, smartphone are fructuous. They are used to send messages, take pictures, make calls, streaming videos, and the likes. But each time you do, your battery drains and there are some apps that continue to drains the battery in the background even if you are not using them.
But with a free app called geeenify, it can save your battery life dramatically.

Greenify saves you battery life by effectively and systematically pushing apps into a sort of “hibernation” mode—an idle state that keeps them from running in the background and draining your battery.
Greenify Features
1. NEW: Set hibernation mode on a per-app basis normal, shallow (root required) or deep hibernation (by Island).
2. The legacy deep hibernation (Xposed) is removed due to reported apps incompatibility.
3. Apps targeting 8.0 are correctly recognized as
“background-free” on Android 8now.
4. Support the official Xposed for Android 7.x.
5. Enhanced wake-up cut-off no longer gets disabled by itself.
6. Improved the compatibility of wake-up tracking.
7. Fixed a bug causing some wake-ups not being cut-off.
Where can I download Greenify PRO?
Greenify has both trial and paid versions which you can get the free on playstore and download the paid version Here