While the Series 6 has a titanium body option, the Series 9 is only available in steel and aluminum. The Apple Watch Series 6 is smaller (40mm and 44mm) than the Series 9 (41mm and 45mm).

Apple Watch Series 4-6 and SE The Series 4 was the first Apple Watch to have a major redesign, with sleeker cases and bigger screens for a fresher look and improved ergonomics. The Series 5 that ...

The Apple Watch Series 5 shared a lot of features with the Series 4, coming with the same bigger display and being available in 40mm and 44mm. Ceramic and titanium case options were added.