The Cupertino-based firm will also update its software to give users more visibility into the health of their iPhone's battery.
Apple has been facing consumer uproar and a slew of lawsuits after it admitted to reducing performance of older iPhones to prevent unexpected shutdowns.
"...We know that some of you feel Apple has let you down. We apologise. 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," Apple said in a lengthy apology note on its website.
Apple further said it has "never and would never do anything to intentionally shorten the life of any Apple product, or degrade the user experience to drive customer upgrades".
Apple is offering a replacement of an out-of-warranty iPhone battery for USD 29 (compared to USD 79 earlier) for users of iPhone 6 or later. This will commence from late January and will be available worldwide through December 2018.
When contacted, Apple India confirmed that the battery replacement will be available in India for Rs 2,000 (plus taxes).
In its note, Apple explained that "continued chemical aging" of batteries in the older generation iPhones contributed to the performance issues after a software update about a year ago.
"We've always wanted our customers to be able to use their iPhones as long as possible. We're proud that Apple products are known for their durability, and for holding their value longer than our competitors' devices," it said.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)