Vibrations: avoid to set vibration on your smart phone for message receive, email receive and reminders.
Darkscreen wallpaper: on smart phone for light colour display required power apart for black screen there is not / less power required
Avoid GPS Tracking : avoid to set on location track on your mobile this feature Tajes lot of battery power.
Main screen widgets : remove unwanted or not required widgets which you are often not used from your screen, because they always try to get latest information from internet which consume your battery power. example weather, news et c.
Airplane Mode: if possible keep your mobile on airplane mode when your are on a poor Network area or travelling on airoplane. Not during this period your phone will be not reachable for every call and message.
Doze mode: android latest update on marshmallow comes with doze mode for this you don’t required to click on any button or option it works automatically at backgbackground. Similarly as hybernate options comes on Windows.
Network Connectivity : check if there is Bluetooth, hotspot and Wi-Fi are enabled keep if not required.
Hotword sound detection : this feature of google For voice search which generally always ready to detect your voice and take battery life so if you not use this keep it disabled go to settings -Google services- search and now feature.
Frequently changing: avoid to charge your mobile frequently this will reduce life of your mobile battery. It is advisable to don’t remove charging till phone get 100% charged. And also try to use it until mobile get 1-10% battery available.
All batteries has a battery charging life count.