The finds come from pdfu, a forum member who has been reading Apple's betas since WWDC, and MacRumors published the breakdown on Monday morning. The clearest of the four is a separate health app called Readiness, distinct from the existing Vitals app, which the watchOS 27 launcher already places in the default Home Screen layout immediately after Workout. Strength workouts gain somewhere to store individual sets, repetition counts, weight, equipment and duration. An optical-sensing family named Sunstone4p0 replaces Sunstone3p75plus, with lower noise coefficients and channel selection based on wrist and orientation. A storage reference points at 128GB, twice what the Series 11 carries.
Two of the four need hardware nobody outside Apple has seen. A new optical family sitting in the operating system says nothing about whether the watch announced on Wednesday has the parts to use it, and there is no guarantee the sensor work launches with Series 12 at all. The same applies to the storage figure on a line that ships 64GB today. Readiness is the safer read, because a place in the shipped launcher layout is a decision somebody already made. Even so, the app is not in the beta itself, and a string found in code does not commit Apple to shipping it.