What is a dual-SIM phone?

Why might Apple be sniffing around dual-SIM?

Among all the leaks and rumours to emerge in the lead up to Apple’s September 12 iPhone event, one feature, in particular, stands out.

We’re talking about dual SIM compatibility, which will likely either seem totally alien or rather old hat depending on which part of the world you live in.

So what exactly is a dual SIM phone? What are the benefits? And why might the SIM-hating Apple consider incorporating this feature into its iPhone range?

What do we mean by dual-SIM?

The clue here is all in the name. SIM stands for subscriber identity module or subscriber identification module. It’s the little integrated circuit, stuck onto a cheap piece of plastic which securely stores and authenticates your unique mobile number.

Dual-SIM phones are phones that contain the capacity to run two SIM cards simultaneously. The SIM card tray of your typical dual-SIM phone tends to be elongated to allow for that extra piece of plastic.

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When it comes time to change your phone, you typically need to transfer your SIM card across to the new device if you want to keep your number (without jumping through a few operator hoops, at least). Such a process isn’t necessary with a dual-SIM phone, though there are still limitations.

In most modern dual-SIM smartphones, both SIM cards operate in a standby state. This means that you don’t have to deliberately switch in between the two to receive calls and texts, but you can usually only actively use one at a time for data usage.

What are the benefits of a dual-SIM phone?

Having a dual-SIM phone means that you can run two mobile numbers and accounts simultaneously from one device.

It’s not uncommon for people in developed countries to have a second phone for work purposes. The potential convenience of whittling this down to a single handset is clear.

A dual-SIM set-up can also be useful for business users who travel a lot in countries with variable mobile connectivity. It means they’re more likely to be contactable regardless of any network-specific black spots.

In many developing countries where fixed-line phones and internet availability aren’t as prevalent, a relatively fractured mobile network environment forms the backbone of the economy. It’s very common for people to run multiple SIM cards on a single device, chopping and changing according to different business and personal needs.

When it comes to the huge Chinese smartphone market, roaming between provinces can lead to costly fluctuations in call charges. Having a second SIM to hand to cover for this is often necessary.  It’s no surprise, then, that dual-SIM phones have become highly popular in such countries.

Current dual-SIM smartphones

As you’ve no doubt ascertained by now, dual-SIM smartphones are not a recent phenomenon. They’ve been on the market for a while now, and not just in developing countries.

Plenty have made their way West, though the UK has been relatively slow to pick up the trend. The power of the mobile operators, who prefer to lock customers into a single plan per subsidised handset, doubtless has much to do with that.

With the increasing popularity of buying cheap unlocked phones online, however, that situation is starting to shift.

Many established phones of the moment, such as the Moto G6, the Huawei P20 Pro, and the Samsung Galaxy Note 9, can be found in both single and dual-SIM guises if you scout around the usual online suspects.

Chinese manufacturers, in particular, have been at the forefront in offering dual-SIM functionality as standard. The OnePlus 6, the Honor 10 and the Xiaomi Mi A2 are all recent global phones that are firmly in the dual-SIM camp.

Why might Apple be going dual-SIM now?

It’s an open secret that Apple hates physical SIM cards, and it’s not hard to see why.

They’re clunky, flimsy, and ultimately unnecessary lumps of plastic. They take up valuable space in Apple’s precious iPhone designs and, what’s more, they exist purely by decree of those slow-moving and stubborn network operators.

So it’s no surprise that we’ve managed to go ten years without seeing a dual-SIM iPhone. Apple even took steps to kill the SIM off with the release of the cellular Apple Watch and second iPad Pro onwards, all of which run on virtual eSIMs.

So what’s changed? Well, the SIM standard is still alive and kicking for one thing. Operators haven’t allowed it to evolve despite Apple’s pushing.

More importantly, though, the absence of a dual-SIM facility is likely hurting (or will soon hurt) Apple’s bottom line. As we’ve discussed, dual-SIM is something users in developing countries demand. Those same developing countries are where the vast majority of smartphone growth is now coming from.

Dual-SIM is a must-have feature in the Chinese market, where Apple has concentrated a lot of its resources in recent years. Indeed, some reports have suggested that Apple’s dual-SIM concession might only apply to the Chinese market.

However limited Apple’s dual-SIM push turns out to be, it’ll be a no-brainer if it means more noughts on the company’s year-end profit sheet.

Even if Apple is successful in ditching physical SIMs at some point in the future, it won’t be for a while yet. As such, we’re likely to see a spike in global dual-SIM phones before the standard goes the way of the headphone jack – with Apple a reluctant participant.