Mach_5’s build uses a Raspberry Pi Model A+, a small touch screen, camera, Wi-Fi adapter, GSM antenna, and a few other parts. It then runs Raspbian with a serious of apps to power the smartphone ...

If you have the Raspberry Pi OS Lite that doesn't come with a GUI, you can still use the command line to connect your Raspberry Pi 4 with an external Bluetooth device. Here's how to do so: 1.