Apple Inc was sued on Thursday by the creator of a once-popular app store that accused the iPhone maker of illegally monopolising software distribution on its own operating system.
Cydia, which was created in 2008, said Apple has "illegally squashed all competition" for its App Store, depriving consumers of the ability to choose where to obtain iOS apps and developers from choosing which distributors to use.
The complaint filed in the Oakland, California federal court is the latest case accusing Apple of exploiting market dominance at the expense of rivals such as Cydia, which said it is on the verge of closing and a possible bankruptcy.
Apple, based in Cupertino, California, said in an email it will review the lawsuit and does not monopolise any market.
It also said that for security reasons it discourages consumers from trying to unlock their iPhones, in a process called 'jailbreaking', to install unauthorised software.
The main rival to iOS is Google's Android operating system, which is used in smartphones from such rivals as Samsung.
Cydia, also known as SaurikIT, was created by software engineer Jay Freeman, and is seeking unspecified damages.
It is represented by the law firm Quinn Emanuel Urquhart & Sullivan, which has represented Samsung against Apple in patent litigation.
Apple has a market value exceeding US$2 trillion.
Other antitrust challenges it faces include a lawsuit filed in August by Epic Games, which makes the game Fortnite.
Epic accused Apple of illegally removing Fortnite from its App Store because Epic wanted to use its own payment system rather than let Apple take 30 percent commissions on purchases. That case could go to trial in May 2021.
Last month, Apple said it would reduce commissions to 15 percent from 30 percent for developers generating US$1 million or less of proceeds from App Store sales.
The case is SaurikIT LLC v Apple, US District Court, Northern District of California, No 20-08733.