Neil S. told me about this.
It has a serial(RX/TX) interface. Also has a SD card interface.
The interesting thing about this is that it comes with Nextion editor, you write the user interface on the PC, then upload to a SD card, and put the SD card on the unit.
I presume what that means is that is the following:
- connect an Arduino, esp8266 or raspberry pi via serial interface
- create desired user interface on the PC with Nextion editor and upload to a SD card
- When you click a button or move a slider on the touchscreen, it sends a message on the serial interface to the microontroller for further actions.