Apple has posted a letter on its website today apologising to customers for slowing down older iPhones.

The tech giant has faced a slew of social media grumblings - and multiple class action lawsuits - after admitting to slowing down the battery life of older iPhones, a move which customers claim has been done in order to generate new sales of its latest iPhone products, according to USA Today.

"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," read the letter.

"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."


Read more: Apple admits to slowing down older iPhones to avoid shutdowns

In the letter Apple explained that a year ago it delivered a software update aimed at improving power management during peak workloads "to avoid unexpected shutdowns on iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, and iPhone SE. ... While these changes may go unnoticed, in some cases users may experience longer launch times for apps and other reductions in performance."

Apple said at first it believed such performance loss was due to a combination of factors, including "a normal, temporary performance impact" when upgrading the operating system and minor bugs.

"We now believe that another contributor to these user experiences is the continued chemical ageing of the batteries in older iPhone 6 and iPhone 6s devices, many of which are still running on their original batteries," the letter said.

At the end of the letter, Apple said it wanted to "regain the trust of anyone who may have doubted Apple's intentions," and plans on doing the following:

• Reduce the price of an out-of-warranty iPhone battery replacement from US$79 to US$29.
• Early in 2018, "we will issue an iOS software update with new features that give users more visibility into the health of their iPhone's battery, so they can see for themselves if its condition is affecting performance."