Shortly after customers begin to receive their Apple Watches and Apple boasts over 3,500 Watch apps are available, Apple made two small changes to the App Store Review Guidelines. The new section 10.7 states that watch apps must do more than just telling time. Also a new requirement on Human Subject Research says that the research should have approval from an independant ethics review board.
10. User interface
Apps that look similar to Apps bundled on the iPhoneiOS or Watch OS devices, including the App Store, iTunes Store, and iBooks Store, will be rejected
Watch Apps whose primary function is telling time will be rejected
27. HealthKit and Human Subject Research
Apps conducting health-related human subject research must secure approval from an independent ethics review board. Proof of such approval must be provided upon request.