In February, 9to5Mac discovered code in a beta version of Apple's iOS 13.4 software referring to an API for something called "CarKey." After finding more extensive code for CarKey in the second beta version of the same iOS, 9to5Mac believes CarKey will be functionality allowing a car owner to lock, unlock, and start their car with their iPhone or Apple Watch. The vehicle would need to be equipped with Near-Field Communications (NFC), the same protocol Hyundai uses for its Digital Key and Tesla uses for its Model 3 keycards. Further CarKey development in a beta version of iOS 14, which included screenshots, points to BMW being the first carmaker to get access to the feature. This sounds reasonable given BMW was the first to introduce wireless Apple CarPlay. When 9to5Mac asked the German automaker about CarKey, a spokesperson responded with, "Please understand that at this point we cannot confirm your request nor give you further details. We would like to refer you to our press release."

CarKey screenshots show several potential ways to implement and use the feature. After pairing the phone with the car's NFC transmitter through Apple Wallet, all permissions are controlled through the wallet. A backup pairing method uses a PIN if the automatic process doesn't work. To unlock, the phone only need be near the vehicle, not removed from a pocket or bag. Prototype screenshots from iOS 14 show three levels of permissions, either Trunk Access, Access Only, or Access and Drive. A CarKey owner can request the app be authenticated through Touch ID or Face ID before use, or enable 'express' use that doesn't ask for proof. The digital key can be loaned to others permanently or temporarily, and be shared through iMessage with individuals but not groups. When the key is shared through an iMessage, the recipient receives the notification, "[Vehicle Owner] invited you to use their [Vehicle Model] with unlock & drive access. This allows you to use your *iPhone* and *Apple Watch* to unlock/lock the car, start the engine and drive."

The press release BMW referenced was issued in December, speaking to the carmaker's work on digital keys for phones and watches. It read, in part, "Providing customers with simple, connected and 'keyless' access to their vehicles has been a key area of innovation. Today, it is already possible to lock and unlock the vehicle, start the engine and share the key with others using the BMW Digital Key (pictured) as part of BMW Connected on the smartphone. But this is only the first step in a global technological transformation being shaped and led by the BMW Group." The automaker is a charter member of the Car Connectivity Consortium (CCC) that released its NFC-based Digital Key 2.0 protocol last November. Version 3.0 is on the way, bringing compatibility with Bluetooth Low Energy (BLE) and Ultra Wideband (UWB), the latter protocol said to open up "passive location-aware keyless access" at the same time as providing "maximum anti-theft protection [to] enable precise localisation between the device and the vehicle."

The Apple iPhone 11 family already supports UWB, so far used for increased AirDrop functionality. The tech firm applied in 2018 to patent technology allowing an iPhone to manage vehicle features, another patent application from last November laying out a system using Bluetooth and Ultra Wideband to locate a device and then exchange a digital key. The question now is when Apple will debut CarKey. The feature could be rolled out during the online-only Worldwide Developer Conference in June.