A U.S. federal judge in California has ruled that Google must revamp its mobile application business, mandating the opening of its Android operating system to competing app stores. This decision is aimed at providing users with more options for downloading apps and making payments.The ruling stems from a 2020 antitrust lawsuit filed by Epic Games, the developer of "Fortnite," against Google. Last December, a jury backed Epic's claims, declaring Google's app store practices to be an illegal monopoly.Judge Ja ...