Apple today announced the Apple Watch Ultra 4, featuring a new S11 chip, a redesigned health sensing system, and a larger battery that Apple says delivers two days of battery life. With improved power efficiency, Ultra 4 offers up to 18 hours of workout tracking with full GPS and heart rate monitoring, or 45 hours in its maximum extended workout mode. It comes in Black and Natural titanium, alongside new band colors and a new titanium Hermès band.