Apple Watch Ultra 4 review: 79-hour battery and new sensors

The Apple Watch Ultra 4 brings the S11 chip, more frequent heart-rate and daytime HRV readings, plus Vitals and Readiness apps. Battery life reached 79 hours in testing, and 10W charging hits 100% in under 90 minutes. It starts at £749 (€899/$799), but key Audio Intelligence features arrive only in late 2026.

• Battery lasted 79 hours in testing; 10W charging reaches 100% in under 90 minutes
• Heart rate sampled every 5 seconds during the day; HRV now measured in daytime too
• Priced from £749 (€899/$799/A$1,349) with the same body and screen as before
• Audio Intelligence and Siri Recap features promised for late 2026