We’ve been hearing feedback from our customers about the way we handle performance for iPhones with older batteries and how we have communicated that process. We know that some of you feel Apple has let you down. We apologize. There’s been a lot of misunderstanding about this issue, so we would like to clarify and let you know about some changes we’re making.
First and foremost, we have never — and would never — do anything to intentionally shorten the life of any Apple product, or degrade the user experience to drive customer upgrades. Our goal has always been to create products that our customers love, and making iPhones last as long as possible is an important part of that.
and Apple explains how battery ages…
All rechargeable batteries are consumable components that become less effective as they chemically age and their ability to hold a charge diminishes. Time and the number of times a battery has been charged are not the only factors in this chemical aging process.
At least it will cost $29 for an Apple battery replacement.