At its 2019 World Wide Developers Conference (WWDC), Apple unveiled its own single sign-in service to compete with similar ones from Facebook and Google — with the promise that it won’t use that information to sell ads or track you, unlike its fellow tech giants. Prosaically called ‘Sign In with Apple’, the service will give users the option of signing up for third-party sites and apps using a unique, disposable email address that automatically forwards to their iCloud email address. Services and apps with which they use this feature won’t know their real email address. Apple said it can authenticate a user using Face ID or Touch ID on their iPhone without turning over any of their personal data to a third-party company.

How will ‘Sign-in with Apple’ work?

When the service is launched (it will be available for beta testing mode this summer, according to Apple’s website), users will have the option to use their iCloud accounts to log in to third-party applications. They will have an option to either let the application see their email address or hide it from them. If they choose to hide it, Apple will auto-generate a random “relay” email address. Emails send to this address will be automatically forwarded to the user’s iCloud email account.

Which devices can use the new feature?

During WWDC, Apple only demonstrated the tool on an iPhone. Sign in with Apple is a key feature of iOS 13, which will be available for iPhones 6s and later models. It isn’t clear at this time if the tool will also work on iPads or Macs, not to mention Android phones and Windows machines. However, Tom’s Guide reported that no iOS or macOS device is needed to use sign In with Apple, so Windows and Android users should be able to use the feature as well, provided they have an Apple ID.

Will Apple’s login option appear in all apps?

Yes. Apple’s terms for developers make that clear. Apple has made it compulsory for all app developers to include the option to Sign in with Apple, which goes to show how much power the company wields over its developers.

What does this mean for Facebook and Gmail?

Users can already sign up for third-party services with their Google or Facebook accounts, but this convenience comes at a price: they have to trust Google and Facebook to keep their personal details safe. The problem is that Facebook and Google haven’t always kept up their end of the deal on privacy, and have used such information to power advertising that is often intrusive. By promising strict privacy, and giving users the option to hide their actually email addresses, Apple hopes its new feature will upend Google’s and Facebook’s, and become the preferred method of signing up for third-party services.

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