c The main display has grown, and a new 64-bit processor is also much faster. Apple has brought a new dial that should be more versatile and include more applications. It also seems to support a shortcut to quickly call your favorite contacts. Other clocks were added, but the company did not pay more attention to them.
New is also the clock control with haptic response. Someone may be interested in installing automatic fall detection. The clock will call SOS with GPS location after a minute (in case you do not respond).
The biggest innovation is the built-in ECG directly into your watch. Apple highlights the importance of ECG, ECG can be monitored, and data will be available in real time for selected businesses or universities.
Speaker is also louder, up to 50% according to the manufacturer. The stamina will be the same as before, according to the manufacturer 18 hours, in practice within 3 days.