iOS 12.1 beta technically enables eSIM functionality for dual SIM iPhone XS4
That’s because iPhone XS and XS Max units sold outside of the world’s largest handset market are unable to physically accommodate two SIM cards at once. Instead, they come with something called an eSIM, which is not an entirely new technology, but now that Apple is embracing it, everyone else will probably follow suit before long.
When the iPhone XS, XS Max, and iPhone XR were formally unveiled, Apple vaguely mentioned dual SIM capabilities would be enabled by a “free software update later this fall.” As it turns out, said update is the 12.1 version of iOS, already confirmed to include the highly anticipated (and sometimes mocked) Group FaceTime feature.
Apart from that, the first public beta build appears to expand on your standard cellular settings to allow adding a plan. Accessing that menu will require scanning a QR code to actually activate the embedded SIM technology or entering a few details manually.
Either way, you’ll need to contact your carrier for information on steps to follow. Currently, Apple’s list of approved wireless service providers supporting the eSIM standard consists of only 14 names across 10 countries, with Sprint likely to also join the party soon enough.
Interestingly, Deutsche Telekom seems to have started granting access to dual SIM functionality for iOS 12.1 beta testers in Germany. Other networks could follow suit in the not-too-distant future, but alas, we have no dates to share.
No iOS 12.1 public release date, and certainly no eSIM activation dates for any specific carriers. In fact, we can’t even be sure the final, stable version of iOS 12.1 will bring the dual SIM feature to the masses. These things are always in flux.