The display is a 8.8 inch , 1920x480 IPS HDMI touch display. bought on aliexpress.
There is a specific part of the PCB to emulate a USB keyboard. It is made of an ATMEGA32U4 at 12 mhz.
The keys are KAILH Low profile also found on aliexpress
The battery charger is a simple 2A LIPO charger bought from aliexpress also.