The Tesla Model X does not support Apple CarPlay and will not play music stored on Apple devices like the Apple iPhone 7 through the phone's Lightning connector. Instead, to play music or make calls from the Apple iPhone 7 through the Tesla Model X, you'll need to use Bluetooth.
You can also play music from YouTube although the album information does not show up on the car's display.
Of course, you can also make calls on the Apple iPhone 7 through the Tesla Model X. You can also use Siri to command the iPhone but any Siri commands would have to be initiated by pressing down the iPhone home button (or just say out loud 'Hey Siri') and you can initiate Siri commands and queries through the Tesla Model X's audio system. Note that if you say 'Hey Siri', for some reason we noticed a long delay before the Apple iPhone 7 responded with a couple short beeps to let you know you can say your command or query. By comparison, the 'Ok Google' command on Android phones with the Tesla Model X was a lot more responsive using the same AT&T network and vehicle.
Note that you also won't be able to use the iPhone's car navigation system on the Tesla display. Also note that calendar and contact information is sync'ed over WI-FI and mobile data connection through the Tesla App (and not through Bluetooth).