California Atty. Gen. Kamala Harris put United Airlines on notice Friday via Twitter.

@KamalaHarris rebuked the airline for not displaying a privacy policy on its mobile app.

“Fabulous app, @United Airlines, but where is your app’s #privacy policy?” she wrote.

She also linked to California’s Online Privacy Protection Act, which requires commercial websites to conspicuously post a privacy policy if they collect personally identifiable information from Californians.

“We have to both cheer the incredible advances in technology and at the same time protect consumer privacy. Atty. Gen. Harris believes the only way to do both is through innovation in oversight. She was proud to strengthen consumer privacy by requiring a privacy policy for all mobile apps, and expects every company to live up to their legal obligations of transparency and security,” Harris’ spokesman Shum Preston said in an emailed statement.