Dual SIM phones: what are they, how do they work, why would you want one?

Dual SIM phones: what are they, how do they work, why would you want one?We’ve had a couple of reader questions about dual SIM phones recently, so I figured I’d flesh out the advice given by our regulars (thanks guys!) into a dual SIM guide of sorts.

Here we’re asking: What are dual SIM phones? How do dual SIM phones work? Why might you want one? And why aren’t dual SIM phones such a big deal in the UK?

Let’s starts with the obvious question: What are dual SIM phones? As the name suggests, dual SIM phones allow you to pop two SIM cards in the one mobile phone. Simple.

In fact, some phones have pushed the boat out further with triple SIM support, including the Samsung Galaxy Star Trios, LG Optimus L1 II Tri, and Acer Liquid E700.

Or heck, how about the Cherry Mobile Q70 Quad? In addition to housing a quad-core processor, it invites up to – you guessed it – FOUR SIM cards.

Sticking two (or more) SIM cards in one phone is all well and good, but why would you want to do that? The answer is loosely fourfold.

Firstly, network costs. Having a dual SIM phone means you can pop in one SIM for, say, minutes and texts, and a second for data. There’s more of a demand for that in emerging markets, where one network might offer appealing rates for PAYG minutes and texts, but be utterly appalling when it comes to data.

As such, imagine using one SIM for your calls and texts, but switching to the second SIM whenever you want to jump on the mobile web. You’re potentially saving oodles of money, and it’s far less onerous than having to constantly swap out the SIMs.

That’s hugely uncommon in the UK, however, where we’ll typically buy a phone on contract and often have the phone locked to a particular network; or, alternatively, we’ll stick a Pay As You Go (PAYG) or “SIM only” SIM in our phones, but shop around for the best deal to satisfy minutes, texts and data (check out our Best UK SIM only deals feature, incidentally).

Similarly, you might struggle with network coverage as you move around the country, and hence a dual SIM phone would be hugely convenient.

BYOD (bring your own device) work situations make dual SIM phones appealing, too. One of my mates carries around an iPhone 6 for personal use and an iPhone 5c for work. Imagine the tri-tone confusion whenever he gets a text. Having one device – a dual SIM phone – would make things significantly more convenient, freeing up an entire pocket in the process.

The fourth reason is travel. Whether you’re going abroad with work for a few days, or travelling indefinitely, a dual SIM phone means you can keep your domestic SIM around, but chuck in a local SIM to avoid international roaming charges.

Of course, Three Mobile’s Feel At Home negates that particular worry for a lot of people (use your domestic allowance abroad in a growing list of countries), but not all UK networks are so generous.

As for “How do dual SIM phones work?”, well, the specifics vary from manufacturer to manufacturer, but features might include the ability to assign a particular SIM to a particular task e.g. SIM 1 for calls and SIM 2 for texts, while some third-party apps include dual SIM functionality.

There are, in fact, three individual types of dual SIM phone, namely passive, standby and active. Passive – or “dual SIM switch” – phones can only have one SIM active at a time; standby locks down the other SIM when making or receiving calls; and active means both SIMs are always active thanks to having two transceivers.

And so ends our dual SIM phone guide. We’ll be back shorly with an in-depth look at some of the best dual SIM phones out there. In the meantime, if you have any questions about dual SIM phones, feel free to ask below.

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 1 comment

Saurabh_gupta_27  Jan. 19, 2015 at 20:27

What is the best dual sim mobile currently in the market?


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