Apple Watch Ultra 4 is expected at the September 9 event, with rumors pointing to significant health sensor upgrades. Digitimes reports the sensor component count will double, and Mark Gurman hints at fitness tracking improvements. A new high blood pressure feature has reportedly been reviewed by the FDA, though details remain unclear.

The new watch will likely feature an S11 chip, the first major CPU upgrade since 2023, designed to support on-device AI features. This aligns with watchOS 27's Siri improvements, potentially making the Ultra 4 the first mass-market AI wearable.

Design rumors are mixed: Digitimes suggests a redesign, but Gurman says no major overhaul is expected. A ceramic case option is possible for the Series 12, but the Ultra 4 may stick with titanium. Ultimately, the Ultra 4 will focus on health, performance, and subtle design tweaks rather than a radical new look.