Iphone 4 battery life is terrible?

My IPhone 4G was jailbreaked on a 4.3.5 version, and tomorrow i have restored him an upgrade to 6.1.3 version, I charged it to 100% at about 00.00 and in the morning about 9.00 am it was on 45% and now 1% is lasting about 2 min if i don't task, if i do about 1 min, yesterday on 4.1.5 it was all ok and now this, is it something in new application or what? What do I do?

I think its because of your brightness

Make sure your brightness is low(just enough so you can see)

make sure you are not using multitask too much (double tap the home button and delete all apps on the bar that comes up from the bottom)

turn off your mobile network if you don't need it at the moment, use other apps to keep in touch, such as viber, rebtel, and skype

turn off Wi-Fi it you are using your mobile network. Or else your phone will constantly keep scanning for Wi-Fi networks that it can join

turn off your phone when you don't need it at all

if none of these tips help then your battery may be worn out.

Iphone as well as most smartphones can function almost as much as a laptop or PC hence, the fast battery drain. To maximize power:

*Turn off location services
*Turn off mobile data services, if you don't need internet
* In SETTINGS - Mail, Contacts, Calendar - Fetch - Manually
*Turn off notification alerts (e.g.facebook, email, etc)
*Turn off Wi-Fi button, to disable auto-connect when a network is in range

Hope this helps!

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