One of the most painful questions for smartphone’s users is  – how to extend the battery life? How to keep the smartphone alive without charging at least 2-3 days? Is it possible at all?
The answer is – Yes, it’s possible. I re-charge my iPhone every 3-4 days. And You can find several tricks how to do it.
I don’t want to iterate through all the battery-killer applications. And I don’t want to highlight well known tips like brightness, usage, etc.

1. Mail Client. 

Usually people have few mail boxes connected to their iPhone. And all the mail boxes are configured to fetch the data automatically each 30 mins. This is main battery killer.
What You can do? I suggest to leave the auto fetching of the mails for the only one of the most important mailbox. Only this trick allows You to extend You battery life for 6-7 hours (tested on my own iPhone)

2. Usage of 4G/LTE.

I’m sure that most of the users have configured the usage of LTE by default. But what happens when the cellular signal is low and not enough for LTE? iPhone uses 3G but also it tries to connect to 4G. And these attempts require the fortification of signal and as result battery usage. My suggestion is to use 3G (sometimes even 2G) mode during the problem with network.

3. Sorry, Facebook, but yes.

The Facebook application is battery killer. I suggest to use the web version of Facebook with Safari. You’ll see that You can save at least 5-6 hours of Your battery life. I know that it could be not very comfortable, especially if You used to use the Facebook authentication for another applications.

4.  Turn Off the usage of applications in background mode.

I was testing the usage of iPhone with turned on and turned off the function of background app usage. And to be honest – I didn’t find any difference except only one – I saved around 4 hours of the battery life.
How to do it: go to Settings -> General -> Background App Refresh and uncheck this feature.

5. Usage of location services (GPS).

When do You need the location services to be turned on? Usually only during the usage of maps or another applications. So, it’s better to turn off the usage of location services in background mode almost for all the applications except applications for tracking of outdoor activity.

How to do it: go to Settings -> Privacy -> Location Services and then need to go through the list of apps and turn off where it’s not required.

6. Human factor. Habit of clicking something in the every free second.

Unfortunately, this “feature” is most difficult to eliminate. But I suggest to try it at least for experiment. You will find that 5 hours of the battery life will be saved.

I’ll be very glad to read some feedbacks about these tips and tricks if it was helpful.