I have an iphone 4, battery keeps dying?

How do i stop my battery from dying even though i aint even using it. I keep my cel in my pocket while i'm working, but when i go take my break its already at 50% but it was 100% when i started working just 2 hours before

Replace the battery.

I don't really have a solution for you, but i do have an idea. Iphones are really good and efficient, but Andriods have a lot of things to take advantage of that iphones don't have. Free music- Any and every song. Literally. Free apps- there are tons of free apps. Battery efficiency- i go to school everyday with my phone on in my bag. (Its an andriod- HTC One X) At the end of the day, i take it out on the bus & its stayed 100% all day. Honest. I think people might get iphones just because they are an apple product & Siri. But Andriods are honestly better. My dad has the same phone as his personal phone, then a Iphone 4 for his work. He says he likes the andriod better because the iphones battery always gets low when he never even touches it all day, it drops calls, and many more things. Andriods are overall better phones. No hate on iphones though. They are great phones too.

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