At WWDC Apple continued to position itself as separate from tech rivals like Google and Facebook on the issue of privacy, unveiling a new "Sign-in with Apple" feature that hides your identity even from developers. So, given the value of collecting information about their users, why would any developer actually include the option in their app? Because they have to, according to the company's refreshed guidelines.

Sign In with Apple will be available for beta testing this summer. It will be required as an option for users in apps that support third-party sign-in when it is commercially available later this year.

At least, if it offers third-party sign-ins as an option (read: Google or Facebook authentication), then it has to include Apple's privacy-focused setup too. These are the same guidelines that now further restrict data collection on apps meant for kids, and they don't stop there.