In addition to the different case sizes, materials, colors and band types, the Apple Watch Series 9 features one of two data systems: GPS and GPS + Cellular.
Apple Watch: GPS vs. GPS + Cellular! (Which Should You Buy?)
We compared the Apple Watch Series 9 GPS and Series 9 GPS + Cellular to help you decide which is right for you.
The Apple Watch with LTE cellular data lets you make calls, stream music, and search the web from your wrist. It also adds a significant cost to the device, but if you take full advantage of the convenience, it may be worth the extra cost.
The GPS + Cellular models of the Apple Watch first became available with the Series 3 in 2017. Previous versions only had a GPS option, but since then everyone has had two variants available.