External displays work just like the old Lightning-to-HDMI adapter: the system will simply mirror the iPad Pro by default, but apps that support an extended screen can do different things. Keynote will use the external display as the presentation monitor and show you the next slide on the iPad, for example. Djay will show visualizers on the second screen. But most apps don’t do anything except mirror, so don’t get too excited about your crazy multiple-monitor iPad Pro rig just yet. All of this is exactly the same as the older iPad Pro, which supported external displays using a Lighting-to-HDMI dongle — the only real changes are that the new Pro can support up to 5K displays, and run a display simultaneously with other USB-C devices.
Keyboards worked. A USB microphone showed up in Garageband. You can plug a phone or Nintendo Switch into it and get up to 7.5 watts of power to charge them. (That’s not really enough for a Switch, by the way.) Apple supports both analog and digital audio out, so virtually all USB-C headphones and audio dongles work, a huge improvement over the Android ecosystem.
