Apple has updated its App Store Review Guidelines to reflect an Apple Watch rule that it's been enforcing over the past several weeks, which prevents developers from creating Apple Watch apps that display the time. According to the newly added 10.7 rule under "User interface," Watch Apps that have a "primary function" of telling the time will be rejected.
Though this rule, noticed first by 9to5Mac, was not previously listed in the App Store Review Guidelines or in the Apple Watch Human Interface Guidelines until today, Apple has previously been using this guideline to turn down Apple Watch apps, and its enforcement of this rule appears particularly strict based on some of the apps that have been rejected.
MacRumors recently spoke to one developer who had his app rejected from the App Store due to the time telling rule, but offering the time was not the main function of the app. Instead, it was an app that used a clock-like face to display sunset/sunrise times along with the position of the sun and the moon.
The developer was told by Apple that Apple Watch apps containing a clock face, the likeness of a clock, or time-telling functionality would be rejected, and the Apple employee he spoke with mentioned that quite a few developers had been rejected due to the policy.
Given Apple's aim to position the Apple Watch as a fashion accessory, it's no surprise that the company is maintaining strict control over what's arguably the most important core function of the Apple Watch -- telling the time. In interviews, Apple executives have explained that hundreds of hours of work went into developing the watch faces that are available for the Apple Watch, with an obsessive amount of detail put into each one for the best possible time-telling experience.
Apple's also advertised the Apple Watch as an "incredibly accurate" timepiece, a claim that it might not be able to guarantee if a third-party time-telling app is allowed to display the time. Watch faces are one aspect of the Apple Watch that Apple is not allowing users or developers to touch. While watch faces can be customized with Apple's options, users cannot select their own backgrounds as they can do on the iPhone or iPad and developers cannot develop their own Apple Watch face experiences.
Apple often has strict rules when a product launches, but the rules can and do relax over time, as we've seen with iOS 8 and the return of the once-forbidden Launcher app. It's possible that Apple will open up watch faces to developers in the future, or become less strict with apps that include time-telling functionality, but for now those types of apps will not make it into the App Store.
Today's App Store Review Guidelines update also included a new bit about HealthKit. Rule 27.10 says that apps conducting health-related human subject research must secure approval from an independent ethics review board.
