By Jonathan Stempel

April 14 (Reuters) - A new antitrust lawsuit on Tuesday accuses Google of shutting out rival Android app stores by ‌monopolizing app distribution and billing, violating U.S. antitrust law.

Aptoide, a ‌Portuguese company that specializes in mobile games and calls itself the world's third-largest Android app store, ​said it would have exerted substantially more pressure on Google's pricing and policies but for Google's "anticompetitive chokehold" that shuts out smaller rivals.

Google, a unit of Alphabet, did not immediately respond to requests for comment.

Based in Lisbon, Aptoide brands ‌itself "the alternative Android app ⁠store," with about 436,000 apps in its catalog and more than 200 million annual users by 2024.

It said it ⁠offers lower commissions to developers and lower costs to users, yet suffers from irreparable harm because Google deprives rivals of exclusive content from top developers, ​and steers ​developers to Google Play and other "must ​have" services.

The lawsuit filed in ‌San Francisco federal court seeks an injunction against alleged anticompetitive practices, plus unspecified triple damages. Aptoide filed a separate complaint against Google with European Union antitrust authorities in 2014.

Last November, Google agreed to make Android and app store changes to settle a five-year-old antitrust case by Epic Games, maker of ‌the popular Fortnite video game .

A jury found ​in 2023 that Google unlawfully stifled competition, ​and the trial judge ordered ​sweeping reforms the following year.

Google has also defended against ‌a U.S. government case in which ​a judge in ​August 2024 found its internet search engine an illegal monopoly.

The judge later ordered the Mountain View, California-based company to share search data ​with rivals, but did ‌not require a sale of its Android operating system or Chrome ​browser. Google and the government appealed.

(Reporting by Jonathan Stempel in ​New York; Editing by Bill Berkrot)