U.S. DOJ demands Apple and Google unmask over 100,000 users of popular car-tinkering app in emissions crackdown

The U.S. Department of Justice is seeking personal data on potentially hundreds of thousands of drivers who downloaded EZ Lynk’s Auto Agent app, escalating a years-long legal battle over vehicle emissions controls. Subpoenas issued to Apple, Google, Amazon, and Walmart request names, addresses, phone numbers, and purchase histories tied to the app and its accompanying hardware.

Background on the Case

The DOJ first sued EZ Lynk in 2021, accusing the Cayman Islands-based company of violating the Clean Air Act by marketing and selling “defeat devices.” These tools allegedly allow users to bypass factory emissions controls on diesel vehicles, primarily through the EZ Lynk Auto Agent app paired with an onboard diagnostic (OBD) hardware dongle.

EZ Lynk strongly denies the allegations, emphasizing that its products serve legitimate purposes: monitoring vehicle performance, applying software updates, and enabling legitimate modifications and diagnostics. The company argues that any emissions-related use is not its primary purpose and falls under user responsibility.

Scope of the Subpoenas

According to a joint court filing earlier this month, the DOJ subpoenaed Apple and Google in March and April 2026 for download and account data on anyone who installed the Auto Agent app. Additional requests went to Amazon and Walmart for buyer information on the physical EZ Lynk hardware. Estimates suggest the total could exceed 100,000 users, Gizmodo reports.

The government says it needs this information to identify and interview witnesses who can testify about how the tools were actually used. It has already submitted forum posts and social media evidence showing some users employing the system to disable emissions controls.

Privacy Concerns and Pushback

EZ Lynk’s lawyers call the requests “overreach,” arguing they go far beyond what’s necessary for the case and raise serious Fourth Amendment issues. “Investigating this claim does not require identifying each person who has used the product,” they wrote. Apple and Google are reportedly preparing to challenge the subpoenas.

Privacy advocates echo these concerns. The Electronic Frontier Foundation (EFF) and Electronic Privacy Information Center (EPIC) have criticized the broad demand for personally identifiable information, noting that most users never read terms of service and may face unintended legal exposure simply for downloading a tool marketed for car diagnostics and tuning.

Car enthusiasts and right-to-repair advocates view the case as part of a broader tension: drivers’ desire to modify their vehicles versus federal environmental regulations. As one expert noted, “People want to modify their cars and always will.”

What Happens Next

The case has already survived an attempt by EZ Lynk to invoke Section 230 immunity (typically used to shield tech platforms from liability for user actions). A judge rejected that defense in 2025, allowing the litigation to continue.

This episode highlights growing government interest in app store data to pursue enforcement actions. Similar but smaller-scale requests have occurred before, such as a 2019 demand for data on users of a gun-scope app. The current scale (potentially 10 times larger)makes it particularly notable.

Apple, Google, and the other companies have not publicly commented. The DOJ also declined to elaborate beyond its court filings. The outcome of any challenges to the subpoenas could set important precedents for digital privacy in regulatory enforcement cases. For car owners using tuning tools, the message is clear: governments are increasingly willing to trace app downloads straight back to individual users.

MacDailyNews Take: The DOJ is overreaching as this would sweep up people who simply used the app to read their vehicle’s trouble codes or for other mundane reasons.

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