There's another perk to updating to the iOS 12.1 beta: the promised iPhone XS and iPhone XS Max eSIM support is now live. Of course, there's a catch.

Apple's eSIM technology allows for dual-SIM-like functionality using two lines at once, and it is in the iOS 12.1 settings now, as first spotted by 9to5Mac. But activating the eSIM still requires carrier support to become functional.

iOS 12.1 beta users can find the eSIM sign-up screens in Settings > Cellular, which has details of their first line linked to their physical, removable nanoSIM that's slotted into their iPhone. If they wanted to add another line to be assigned to their eSIM, they’d click on “Add Cellular Plan.” 

That brings them to a screen where they can scan a QR code provided by their carrier, or they can click “Enter Details Manually” at the bottom of the screen. Even though users can get this far in the iOS 12.1 beta, without carrier support, they can’t really use this feature.

Carriers will support dual lines...eventually

At the event introducing the new smartphones, Apple noted that three big US carriers (AT&T, Verizon and T-Mobile) had already signed on to support dual lines, as well as non-US carriers like Vodafone, Bell and Deutsche Telekom. 

None have revealed when users can add a line on their eSIM, though it will likely be after the iOS 12.1 update is officially released. That launch date may come next month alongside the iPhone XR launch on October 26. 

We know even less about how the iPhone XS that Apple is producing exclusively for China, which will have two physical ports for nano SIM cards, will be supported by local carriers. As far as we know, that version won’t be available elsewhere.

• How to download iOS 12 today

The LG V40 is poised to be the latest smartphone with three cameras in the back, and it'll be join be two front-facing cameras in the front, according to a new leak.

That's right, the LG V40 appears to offer five cameras in one Android smartphone, as exhibited by a new official-looking press render from noted leaker Evan Blass.

This isn't a big surprise – we've seen LG V40 leaks before. But today's photo is the clearest view we've had of the front and back of the phone – and its many cameras.

LG V40 to best them all?

The LG V40 is out-camera-ing the Huawei P20 Pro, which features three cameras on the back, but only one camera in the front. That's so early 2018.

While the camera use cases remain a mystery, the the recent LG G7 we tested and last year's LG V30 uses a dual-camera setup on back to offer a super wide angle option. Other phone makers – Huawei, Apple and Samsung – have offered telephoto lenses with 2x optical zoom (3x in Huawei's case).

LG could provide the best of both ideas, and give us the super wide angle abilities of the LG V10 that we liked from its second front-facing lens. It was missing from the LG V20 and LG V30.

We'll know more than what this leaked press render tells us on October 3. The LG V40 is set to launch at an LG event that Wednesday, and TechRadar will be there covering it live.

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