Okay, Apple's CarPlay which announced earlier, is not just an iOS software, but it runs together with QNX infotainment system in the car. It is confirmed by QNX’s Paul Leroux (read here). Apple is listed as one of the partners of QNX. (check here)
What is QNX? Many users and consumers know little about QNX, especially before BlackBerry acquired QNX in 2010 to build BlackBerry's tablet. QNX is a unix-like operating system (or should I say POSIX?), it is small and fast. There are sources saying that QNX is just about 100k lines of source code. QNX has been there for many years (since 1980s), so it was proven that QNX is stable.
QNX is a real-time operating system as well. Real-time means the system will response in expected time frame. Since QNX is small and fast, it was used in embedded devices, a good example will be network routers. I heard QNX was used in nuclear plant system as well.
Back in year 2000s, QNX release a demo version of their software which can fit into 1 (or 2?) 1.44Mb diskette. The system includes the OS, a GUI (like X-Window) and a browser which works on an Intel platform. It doesn't matter for today's environment as mobile phones and embedded devices storage are counted by gigabyte, but it is a breakthrough at that time as the Palm PDA is 16Mb (not gigabyte) in size.
QNX runs on many hardware devices includes Intel and ARM (which is more than enough). BlackBerry bought QNX to build their tablet (and mobile platform). The BlackBerry tablet failed, but QNX is still strong in some embedded devices, eg. car infotainment system (the car dashboard).
Now it make sense that Apple CarPlay works together with BlackBerry QNX. QNX is stable and proven as a real-time system, needed to monitor the various status of the car. QNX is strong in car infotainment system. Apple iOS as a feature rich system (eg. Siri voice interface), can just plug in and work together will QNX infotainment system as a good match.