The lawsuit targets Delta's 'Fly Delta' app for smartphones and other electronic devices. The app allows customers to check in online, view reservations and book flights, collecting significant personal data from users, including the user's name, phone number, email and geographic location.
Delta could not be immediately reached for comment Thursday evening.
"Losing your personal privacy should not be at the cost of using mobile apps, but all too often is," Attorney General Kamala Harris said in a statement.
"California law is clear that mobile apps collecting personal information need privacy policies, and that the users of those apps deserve to know what is being done with their personal information."
The case is People v. Delta Air Lines Inc., in California Superior Court, San Francisco, 12-526741.
(Editing by Edwina Gibbs)
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