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July 30, 2014

Smart Dual SIM on Lumia explained

As much as we’d love you to buy multiple Lumias for your multiple SIM’s, there’s really no need with Smart Dual SIM- as we’ll explain.

The latest Lumia 530 as well as the Lumia 630 are equipped with two SIM slots, but they are not just ordinary Dual SIM phones, they’re Smart.


But what makes them smart?

“Historically, if you had a phone with two SIM cards and you were on a call on one SIM, any call to the other SIM would be missed and you could easily miss an important call”, explains Eero Penttinen, Lead Program Manager at Microsoft.

“This obviously isn’t ideal. But, with Smart Dual SIM, you’re reachable on both SIM cards, at any time.”

There’s still only one radio inside the phone, but calls are managed using call forwarding, which we’re all familiar with.

“Let’s say you’re on a call on SIM one and you receive a call on SIM two. Rather than the caller hearing a dead tone, the call to the second SIM will be forwarded to the first one, connecting the calls.”

The same thing happens the other way around, too. No matter which SIM is activated, the other one will divert any communication between the both of them.


Why would you want two SIM cards in the first place?

There are a number of reasons, but Eero’s first suggestion is one of money.

“It’s gaining in popularity around the world, but Dual SIM has been in high demand in many countries for a while now, particularly in markets where reception and the deals people get on their tariffs can really vary.”

“You can really cut down on the calling costs. With two SIM cards on different networks or plans, it may be cheaper to use one SIM over another when making a call internationally, or just to friends on different networks.”

And then there’s the always being connected:


“With two different SIMs on different networks, there’s a greater chance you’ll be able to make or receive a call, no matter the network coverage.

In some parts of the world, this isn’t necessarily a problem, but for many finding a strong signal can be a challenge. This helps.”

Another reason is maybe a bit more obvious:

“Plenty of people now carry two phones; one for work and their own personal one. Owning a Smart Dual SIM phone means you can make some space in your pocket and leave one phone at home.”

If you’ve never used a Dual SIM phone before, you may think that managing your contacts and making calls from different accounts on one phone may be difficult, but it’s not – as Eero continues.

“On the Start screen of the Lumia 530 or Lumia 630 you’ll find two sets of phone diallers and messaging tiles, one for each SIM, and both sets are colour-coded.”

If different shaded tiles weren’t enough, it’s also possible to change the names of the SIM cards. Maybe ‘Work’ and ‘Personal’ might be appropriate. These names are then displayed on the tiles.

“Within each contact you’ve also got the option to call from SIM one or SIM two,” continues Eero.

Not only that, but if you want to always call your boss from SIM two, you can make that the default for that contact.

Are your pockets bulging with two phones? Maybe Smart Dual SIM is what you’re looking for.