You could be eligible for an iPhone battery replacement

Check to see if you are eligible for a new battery

Apple has set up a website for customers to check to make see if their phones are eligible for a new battery.
The company says a "very small percentage" of iPhone 5 users may experience problems with the life of the battery in the phone or have a phone that needs to be charged more frequently than it should.
Only certain iPhone 5 smartphones are eligible for a new battery.  The phones must have been sold between September 2012 and January 2013, and the impacted phones are in a certain range of serial numbers.
Click on the website set up by Apple to make sure your phone is not impacted.