Meta called out Apple’s control of the mobile app ecosystem, and its advertising restraints, in a memo sent to U.S. regulators this week.

The parent of Facebook and Instagram was one of the companies that submitted a response to a request from the National Telecommunications and Information Administration, which in April asked for opinions from tech companies and interested parties about competition in the mobile app ecosystem. Meta sent a 19-page memo outlining grievances with Apple, showing how tech companies are fighting over the future of regulations in Washington.

“Despite having some of the most popular apps in the world,” Meta’s letter to the NTIA said, “Meta’s ability to innovate on its products and services and even reach its customers is determined, and in some cases, significantly limited, by the most popular mobile operating systems, such as Apple’s iOS.”

Meta has been vocal in its opposition to Apple, especially since the iPhone maker implemented anti-tracking protocols into the mobile app ecosystem. Last year, Apple’s App Tracking Transparency framework [ATT] disrupted the mobile ad industry by requiring app developers to get direct permission from consumers to collect data about their web habits. Apple has been making these changes in the name of privacy, but rivals like Meta claim the move gave an advantage to Apple’s businesses, including ad sales. Apple has never been a significant player in advertising, but since it instituted anti-tracking, it also has started to develop its own ad tools to serve brands and developers.

“Apple’s ads business has already witnessed ‘explosive growth’ as ATT has hobbled its competitors,” Meta said in its note to the NTIA.

Apple responded to Meta’s opinion on the app ecosystem, calling the App Store an “unprecedented engine of growth.” In a statement, an Apple spokesperson said that "Apple believes in vibrant and competitive markets and through the App Store, we’ve helped millions of developers around the world turn their brightest ideas into apps that change the world. Today, third-party apps, including Facebook, Instagram and WhatsApp, are among the most popular apps on the App Store. We have every interest in supporting a robust developer community.”

Apple also defended its iPhone software policies on the grounds of privacy. “We believe that a user’s data belongs to them and they should get to decide whether to share their data and with whom,” the spokesperson said. “App Tracking Transparency gives users the choice whether or not they want to allow apps to track them by linking their information with data from third parties for the purpose of advertising, or sharing their information with data brokers. These rules apply equally to all developers, including Apple.”

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The executive branch, with the Department of Justice and Federal Trade Commission, has been investigating competition throughout the internet ecosystem. Meta is under scrutiny for alleged anti-competitive practices in social media. The Justice Department is looking into Google’s hold on the internet ad markets. And there have been rumblings of anti-trust action against Apple.

It’s unclear whether Meta will command much sympathy with its position, but there have been independent developers and smaller companies caught in Apple’s grip, too. App developers, especially ones that rely on advertising, have seen declines in revenue.

Gaming app developers have also criticized Apple for its App Store fees. In 2020, Epic Games, the maker of “Fortnite,” sued Apple over its App Store fees and policies. Apple has always said that its fees help to maintain innovative devices and software, and that its policies are meant to keep its devices secure.

Meta’s note to the NTIA mostly focused on the advertising disadvantages, though. Meta referred to Apple’s mobile marketing programs that would be familiar to most advertisers, including the SKAdNetwork, which was a platform Apple created in order to allow apps to view some data about ads on their properties, but Meta said it was limiting. “SKAdNetwork, Apple’s tool for attributing app installations by users who decline to opt in to ‘tracking,’ drastically limits businesses’ access to data they need to measure and optimize the effectiveness of ad campaigns,” Meta wrote. “Among other things, SKAdNetwork does not support ad-creative metrics, provides data on a delayed and highly aggregated basis, and supports only a limited number of ad campaigns. Apple has also made sudden and unannounced changes to SKAdNetwork, rendering it an unreliable basis for ad measurement and optimization.”

The NTIA was not immediately available for comment about what actions it could eventually take after studying the mobile app landscape. A lobbying group, the Computer and Communications Industry Association, which counts Apple, Amazon and Google as members, submitted an opinion that said the app markets were competitive. “Growth and innovation in the mobile app ecosystem, together with rapid advancements in the power and diversity of mobile devices, have created a fiercely competitive environment,” industry association said in its submission.