FAQ on how Sign In with Apple works based on information at WWDC, including details about two-factor authentication support and private email relay service
One of the bigger security announcements from Apple's Worldwide Developer Conference this week is Apple's new requirement …
Context & Ripple Effects
The FAQ lands days after Apple's debut of Sign In with Apple at WWDC 2019, where the company made the button mandatory for any iOS app that offers third-party logins. The service masks user email addresses through a private relay, and TechCrunch's framing of the week was that Apple is transforming into a privacy-as-a-service company, with sign-on as its flagship feature.
The two-factor detail has a longer arc in Apple's own coverage: Apple [[a:830839|dropped the Recovery Key when it rebuilt two-factor authentication for El Capitan and iOS 9]] in 2015, and in February 2019 it forced all Developer Program members to enable 2FA on their accounts. The FAQ's 2FA section is Apple extending that account-security posture to the login service itself.
First-order effects
- Developers shipping iOS apps with third-party login buttons must now add Sign In with Apple alongside them, and users who choose it receive a relayed email address instead of their real one.
- The private relay service immediately changes what app makers receive at signup: a masked address routed through Apple rather than a direct user email.
Second-order effects
- Login providers whose buttons appear across iOS apps face a mandated rival positioned at parity inside their distribution channel, pressuring them to match the privacy pitch or lose the default slot.
- Relayed addresses weaken the direct email relationship apps rely on for re-engagement and marketing, shifting a slice of the user-contact channel to Apple's infrastructure.
Third-order effects
- If the pattern holds, Apple keeps productizing privacy as a platform layer — the same playbook that later produced Private Relay and Hide My Email in Craig Federighi's 2021 privacy feature set — making privacy features a competitive differentiator for operating-system owners rather than an app-level add-on.
The trend: Apple is turning privacy from a settings page into a paid-platform service, with sign-on and email masking as the wedge that pulls developers and users into its account infrastructure.