Why Do Smartwatches Need a SIM Card?

The World on Your Wrist

Although most smartwatches are an extension of the smartphone to which they are synced, there are some models that can work as a standalone device. These smartwatches are fully functioning phones and communication facilitators, independent of any phone or tablet, but to have complete connectivity, they need to have a SIM card installed. You may be wondering: why do smartwatches need a SIM card?

Why do some models have them while others don’t? And what is a SIM card, anyway? Fear not, friends — we’re here to answer those questions and more to help you understand a little bit more about the shiny, expensive piece of hardware that adorns your wrist.

First Things First: What’s a SIM Card?

why do smartwatches need a sim cardIt may sound like it has something to do with a video game in which you get to be an alternate digitised version of yourself, but actually, a SIM card is a small chip that allows your smartphone or connected smartwatch to function as a communication device on a cellular network.

SIM stands for Subscriber Identity Module, and contains information about the mobile carrier and the name on the contract (so the carrier knows who is paying for voice or data minutes). It also contains phone number information, and it typically stores contacts as well.

If a real world example will help you to understand what a SIM card is, consider this: an iPhone without a SIM card is just an iPod. It can still function in a limited capacity as a digital device, and it may even have wifi and BlueTooth connectivity, but without a SIM card, you can’t take calls on it, send text messages, or use the internet when you’re out of wifi range.

The SIM card in any device connects to its carrier’s cellular network using unique identification data and an authentication key. It’s a small bit of information, but your smartphone or standalone smartwatch won’t have connectivity without it. These identifiers, by the way, are what prevents it from connecting to other carriers’ networks, and they’re also what prevents your device from sending or receiving communication if your account is well past due.

Finally, SIM cards come in three main sizes: standard, micro, and nano. There is a fourth full size SIM card, which is closer to the size of a credit or bank card, and there are also embedded SIMs that are hardwired onto a device’s circuit board. All of these sizes perform the same functions.

Why Do Smartwatches Need a SIM Card?

There are several smartwatches that do use SIM cards, such as the LG Watch Urbane 2. Additionally, there are some smartwatches designed for kids that utilise SIM cards to facilitate better parent-child communication and safety, like the LG GizmoPal2 and Tinitell. Plus, the most recent iteration of the Samsung Gear S2 uses an eSIM card, which is built into the device and affords the user a lot of flexibility in terms of carrier and pricing.

However, the majority of smartwatches, including fitness trackers, high end workout watches, and even the most recent versions of the Apple Watch and Pebble, do not use SIM cards. Instead, they rely on a synced phone within range for its communication capabilities.

To SIM or Not to SIM?

This discussion on why smartwatches need a SIM card brings up a very important question: should you buy a smartwatch that uses a SIM card, or should you get one that doesn’t have one and instead relies on a synced smartphone in close proximity? The answer is a highly personal one, and surprisingly, it’s not all that dependent on the initial purchase price: smartwatches with SIM cards aren’t necessarily more expensive than those without SIM cards.

Cost does factor in the ongoing cost of your device, since if you have a smartwatch with a SIM card, you’ll be on the hook for ongoing fees for mobile data. You’ll also want to consider things like the convenience of having a communication device on your wrist without having to take along your smartphone, as well as individual devices’ other functionality.

Do you have a smartwatch that uses a SIM card? If so, would you recommend it over models that rely on a connected smartphone? Please leave us a comment and share your thoughts!

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There are 5 comments

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  1. Beverley

    I’ve got a smart watch but it needs a sim does it have to be the same sim and number that’s in my mobile phone or can it be any one

  2. Linda Cunneen Ayles

    Linda Cunneen Ayles
    I’m having problems getting just a SIM card for my GT 08 Watch
    Can you get a free card or one that is not so expensive also what size SIM card is it a mini.?

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