Tag Archives: iOS

Fixing dual-SIM provisioning for T-Mobile and GigSky

When Apple announced dual-SIM support for the new iPhone XS, I immediately decided to buy one instead of the iPhone XR that I really wanted. My reasoning was simple: both the XS and XR had a much improved camera, but the XS would allow me to provision a data-only SIM for my international travel. I ordered one and happily started using it, even knowing that dual-SIM support wouldn’t be available at launch.

It’s important to understand what Apple actually supports: you can have one or two SIMs in your iPhone XS or XS Max. One of them may be a physical SIM; the other is a virtual SIM called an eSIM. There’s no requirement that the eSIM be data-only; you can have two phone numbers, provided by two different carriers from two different countries, if you want. All I wanted was international data, so I planned to buy an eSIM from GigSky. Keep in mind that, as of this writing, only a handful of carriers support eSIM. For example, T-Mobile in the US won’t sell you an eSIM, but T-Mobile in Austria will.

It’s also relevant that this phone came from Apple’s iPhone Update Program (IUP). IUP phones aren’t locked to a particular carrier, or at least they aren’t supposed to be.

I downloaded the GigSky app, bought a plan, and tried to flip the switch that enables the secondary SIM. No dice– when I did, the phone screen briefly flashed up the “Hello!” activation screen, then I got a dialog that said, simply, “Actication required.” Not super helpful.

After trying a few random things, like rebooting the phone, I filed a support ticket with GigSky. “Your phone must be locked,” they said. “Contact T-Mobile.”

So I did; TMO looked up my IMEI and said “nope, we don’t have it locked. Call Apple.”

So I did. Apple fooled around for a bit, had me try removing the existing GigSky eSIM and readding it (which you can’t do; I had to buy another one), then told me to verify that T-Mobile supports eSIM. As I mentioned earlier, they support using eSIMs on phones locked to them (which this one wasn’t anyway), but T-Mo US can’t sell you one– not relevant in this case.

I then called Apple back and spoke to a very helpful gentleman named Matt. He suggested that I back up the phone and erase it, then reactivate it, to force it to get a new activation profile. I dutifully did this, whilst sitting in my Swiss hotel room. After a long cycle of reset-related stuff (new FaceID, resyncing with my Apple Watch, &c), I bought a third GigSky eSIM and was able to activate it without error. The picture below tells the story: I’m roaming on Swisscom (through T-Mobile’s normal international roaming for voice and SMS) on my primary SIM (thus the small “P” icon) and using GigSky for data.

Long story short, Apple still has some work to do to make this process work more smoothly, but I am hopeful they and their carrier partners will file down the rough edges to make it less painful in future.

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