Wireless CarPlay for CarPlay enabled cars
Assume that you have Carplay enabled car (full list of car models can be found here: https://www.apple.com/ios/carplay/available-models/). But most of them only allow you to use wired connection. It's OK during long distance trips (you can power up your battery) but very inconvenient when driving short journeys.
The whole idea is to use Raspberry Pi hardware which will be connected to the USB port (Carplay enabled port) and your iPhone will use Bluetooth and WiFi connection to the RPi. This software will take care of BLE and WiFi connection and pass all data to your head unit via USB port.