Nextion are a range of HMI displays with built in controller that can be used with any microcontroller via a 2 pin UART interface. We have some resources here.

Installing Nextion Arduino Library

Download ITEADLIB_Arduino_Nextion from GitHub

Rename the “ITEADLIB_Arduino_Nextion-master” folder to “ITEADLIB_Arduino_Nextion”.
Move it to your Arduino IDE installation libraries folder.

Configuring the library for your Arduino

http://docs.iteadstudio.com/ITEADLIB_Arduino_Nextion/index.html