Here are the differences between a cellular and GPS-only Apple WatchTethered
Apple Watch GPS
From $199 at Apple
Pros
Less expensive
Store music onboard
Lightest weight of all models
Longer battery life
Cons
Must keep iPhone nearby
Only comes in aluminum
Does not support Family Setup
The Apple Watch GPS (Wi-Fi only) model is the least expensive and lightest weight of all models in the line. You get a longer battery life, but that's because it doesn't have a cellular chip. It requires an iPhone for daily use.
Free bird
Apple Watch GPS + Cellular
From $329 at Apple
Pros
Apple Music streaming support
Aluminum and Stainless Steel models
Leave your iPhone at home
All models come with 16GB-32GB of storage
Works with Family Setup
Cons
Most expensive model
No version for Series 3
The GPS + Cellular model allows streaming of Apple Music and the Podcasts app. Series 4 has 16GB of storage, while Series 5 and 6 include 32GB of storage, and you can get all versions in aluminum, stainless steel, and titanium. Series 6 supports internation...
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Here are the differences between a cellular and GPS-only Apple Watch