I noticed that there is a cellular version of the Watch. If I already use an iPhone I do not need cellular on my watch if my iPhone is always somewhat close to me....correct?
iMac, OS X El Capitan (10.11), Late 2013
Hi
You do not need the built-in cellular feature on Apple Watch Series 3 (GPS + Cellular) if your watch is always used with your iPhone nearby.
However, you may still wish to consider buying a Series 3 (GPS + Cellular) model, as they can still be set up and used without enabling the built-in cellular feature. Other differences between Series 3 (GPS + Cellular) models and Series 3 (GPS) models include that (GPS + Cellular) models:
More information is detailed below.
Models
Alongside Apple Watch Series 1, there are two different versions of Apple Watch Series 3:
Apple Watch Series 3 (GPS) and Series 1
Apple Watch Series 3 (GPS) and Series 1 models do not have built-in cellular capabilities. Any data consumed by Apple Watch Series 3 (GPS) is consumed either via the paired iPhone (including Wi-Fi and cellular data) or via a direct connection between the watch and a compatible Wi-Fi network (when the watch cannot connect to the paired iPhone via Bluetooth).
A separate cellular plan for the Apple Watch is not required. An iPhone 5s or newer model of iPhone is required, running the latest version of iOS.
Apple Watch Series 3 (GPS + Cellular)
In respect of calls and data usage, Apple Watch Series 3 (GPS + Cellular) also always first tries to use the Bluetooth connection to your iPhone (which does not require a separate plan for the watch) or, in the absence of that, any available connection to a compatible Wi-Fi network.
If neither of those is available, then Apple Watch Series 3 (GPS + Cellular) has a built-in cellular capability that, under certain circumstances, can enable calls and certain other features, which are not available on GPS-only models, to remain available when the watch is used without the iPhone nearby.
In order to be able to use the built-in cellular feature, you would require a carrier service plan for your iPhone that specifically includes support for the Apple Watch, including the carrier first activating the device on the plan:
Apple's list of supported carriers is here:
Apple Watch - Carriers - Apple
Apple Watch Series 3 (GPS + Cellular) can also be used without enabling the built-in cellular feature, in which case it functions like a GPS-only model and can be used in conjunction with a service plan for iPhone 6 or newer model of iPhone, running the latest version of iOS, from any carrier, with no need to activate the watch on the plan.
Both
The functions that are available on your Apple Watch when it is away from your iPhone depend on various factors including:
About Bluetooth, Wi-Fi, and cellular on your Apple Watch - Apple Support
Features and requirements that apply under various circumstances are detailed here, including within the footnotes:
How to use your Apple Watch without your iPhone nearby - Apple Support
A "short version" is already provided within the first sentence of my previous reply.
If not using the cellular model (or if using it without enabling the built-in cellular feature), the ability to make and receive calls is also not necessarily limited to when your iPhone is within Bluetooth range.
You could potentially still use your Apple Watch for calls even if your iPhone is, for example, one hundred miles away.
Whenever it cannot connect to the iPhone via Bluetooth (range is normally around 33 feet / 10 meters, but this will vary in practice due to wireless interference), it will attempt, as a fallback, to connect to a trusted Wi-Fi network.
A trusted Wi-Fi network is a compatible 802.11b/g/n 2.4GHz Wi-Fi network (some exceptions apply) that your iPhone has connected to before whilst your Apple Watch was connected to the iPhone via Bluetooth.
When instead connected to Wi-Fi, the watch also still offers a number of features, including receiving and sending messages via iMessage.
If your carrier offers Wi-Fi Calling and it is supported on your plan and enabled on your iPhone, you can also use Apple Watch to make and receive calls and (subject to carrier support) to send and receive SMS / text messages.
All of this is explained within the support resources linked in my previous reply, including:
Giving you the short version, if your phone is always within BlueTooth range (about 10 metres) you can make calls on the GPS-only version. However Jonathan UK points out some other potential advantages for getting the cellular model.
Do I need cellular on Watch when I call through my iPhone?
