Setting it up is really easy.

With the BlueDisplay library you create the GUI for your application, e.g. Graphics, Text, Buttons, Sliders and Charts on the Arduino itself. No Android programming required! The Arduino is connected ...

I purchased one of each of these cheap sensors recently from aliexpress for testing purposes. Compared with the ubiquitous HC-SR04 (*), I liked the idea of having a combined emitter/receiver, i.e.

How microcontrollers and single-board computers coordinate high-speed RF acquisition and generation. How SCPI and UART commands let simple controllers use advanced measurements without FPGA ...