Following Apple Inc.'s (AAPL) admission that it purposely slows down the performance of older smartphones, Stefan Bogdanovich and Dakota Speas have filed a class action lawsuit against the tech giant in California. According to the filing, reported on by CNBC, the plaintiffs say they "never consented" to allow Apple to slow their iPhones. 

"Defendant’s wrongful actions directly and proximately caused the interference and loss of value to Plaintiffs and Class Members’ iPhones causing them to suffer, and continue to suffer, economic damages and other harm for which they are entitled to compensation," says the filing. Bogdanovich and Speas allege that they have had to purchase new iPhones and batteries because of Apple's policy. They are seeking certification of a class to cover "all persons residing in the United States who have owned iPhone models older than iPhone 8."

Primate Labs, a company whose apps measure the speed of iPhone processors, published data this week confirming suspicions that the performance of Apple smartphones quickly deteriorate over time. The findings sparked an outcry and led many users to suggest that the tech giant intentionally lowers speeds of iPhones after a few years of use to force customers to upgrade to the latest model.

On Wednesday, Apple acknowledged that Primate Labs's data was no coincidence. However, rather than being part of a sinister plan to squeeze more cash out of customers, the company claimed that its controversial software is used to prolong the life of older iPhone models.

Without algorithms in place to slow down the processor, Apple warned that older iPhones would frequently shut down. These shutdowns are caused by processors working faster than aging lithium-ion batteries can handle, the company added. 

"Our goal is to deliver the best experience for customers, which includes overall performance and prolonging the life of their devices," Apple said in a statement to TechCrunch. "Lithium-ion batteries become less capable of supplying peak current demands when in cold conditions, have a low battery charge or as they age over time, which can result in the device unexpectedly shutting down to protect its electronic components."

Apple said it introduced the feature last year for the iPhone 6, iPhone 6s and iPhone SE. The Cupertino, California-based company now plans to expand the program to more handsets, including the iPhone 7. (See also: Apple Downgraded to 'Neutral' at Instinet.)

“Last year we released a feature for iPhone 6, iPhone 6s and iPhone SE to smooth out the instantaneous peaks only when needed to prevent the device from unexpectedly shutting down during these conditions," said Apple. "We've now extended that feature to iPhone 7 with iOS 11.2, and plan to add support for other products in the future.” (See also: iPhone X Seeing 'Very Strong Demand' in China: RBC.)

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