There is no doubt that the big iPhone 11 upgrade comes down to the camera, as the hotplate on the back can attest. Among the cool new features that Apple demonstrated, was the ability to shoot several simultaneous video streams with the different sensor/lens combos on the handsets, including the selfie-snapper.
iPhone XS and XR predecessors. Heck, even the 2018 iPad Pro with its puny camera kit will be getting it.Since this actually is a feature of iOS 13, and Apple has produced a dedicated API for developers to utilize multi-camera recording since June, it turns out that we might see this option trickle down to the
The way this will be done is by utilizing a third-party camera apps like Filmic. Apple even demoed the Pro version of the app when announcing the iPhone 11 crop, with what seemed to be four streams filming simultaneously on all cameras. Needless to say, this won't be the case on your oldie but goldie iPhone XS or XR, as Apple's multi-camera matrix for the iPhone XS below shows.
As you can see, only two of the cameras on the 2018 iPhone can record at once with the respective quality. Developers can apparently use the main rear camera and the telephoto one for some dual footage shenanigans, similar to the Dual-view Video option that Huawei offers on the P30 Pro. They could also use the main and the front cameras at once for your amazing Instagram story.
What they can't do, however, is utilize three cameras at once, while on the iPhone 11 trio they can, but we'd imagine that won't be a dealbreaker, since the scenarios where you'd want to have more than two simultaneous video streams, are few and far between anyway.