Why is my iphone dying at 15% battery life?

It started with my phone dying at 5%. I could handle that. But then it started dying at 7%, 10% and now it is dying at 15%. I have no clue what to do now! I have an Iphone 4 and I have NOT updated to IOS 7. What could be the issue of this?

Simply your battery is old, search for battery replacement services on ebay or buy new phone.

Since it's an iphone, you should buy a new one

Your battery is old. Just go on amazon and get a new one. No more than 15 dollars for one. Don't pay someone to put it in! It is very simple. Just 4 screws to unscrew and your done! (Look up instructions on YouTube)

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