In this article, I discuss Bluetooth Low Energy (BLE) and demonstrate its basic implementation structure on the ESP32. I also cover how to create a Smartphone app on Thunkable which connects to the ESP32. Working with BLE can be challenging when using libraries and drivers from the manufacturer of the microcontroller (MCU). It can also be difficult to create a smartphone app to connect your BLE device, as it requires understanding mobile software development. I’ll show a straightforward method to get something up and running, and what’s possible with BLE development.