Android and Arduino Bluetooth communication | Matt Bell's Blog
Amazon.com: Kinivo USB Bluetooth Adapter for PC BTD400 (Bluetooth 4.0 Dongle Receiver, Low Energy) - Compatible with Windows 11/10/8.1/8/7, Raspberry Pi, Linux, MacOS, Laptop & Headphones : Electronics
SAE J1939 to Bluetooth Gateway With 9-Pin Deutsch Connection Cable
Tunnel - Reading of analog and digital inputs and switching of relays from an Android app via Bluetooth and GPRS/3G - Webdyn