We are developing a wireless display which combines Nextion touch screen with Wemos D1 mini.
As it's uses standard protocol like http / mqtt, can be used by raspberry pi or other application. Examples of use cases are here
I hope that it will be useful for everyone here!
It's currently available as awards in kickstarter or search for "Wireless display" in kickstarter
Using the Nanomesher HMI (Nextion display and Wemos combined), we have built several example projects: