Hi
Who can tell me about the Phantom 4
what size for the motor....? kv.....?
max distance and max hight for fly ?

Hi, John, http://www.dji.com/product/phantom-4/info#specs   FYI

I just buy a phantom 4 , can I change of the hdmi output module on controler

john.chan Posted at 2016-4-6 11:43
I just buy a phantom 4 , can I change of the hdmi output module on controler

sure can,   dji hdmi module says it can be installed on the P4 so you can install it on the p4

http://store.dji.com/product/phantom-3-hdmi-output-module

HDMI Output Module (Phantom 3 Pro/Adv/Phantom 4)

here is the overview from the page about this product  underlined and made bold inportant section of overview of product to help answer your questions

The HDMI Output Module allows your Phantom 3 Professional/Advanced or Phantom 4 remote controller to output to an HDMI device, such as a screen or goggles.
This module allows for HDMI output from the Phantom 3 Professional/Advanced or Phantom 4 remote controller, similar to that of the HDMI output on the Inspire 1.

Live video feed, iOSD and the aircraft’s battery levels can be exported via the HDMI Output Module.You can also choose to switch off the data display in the DJI GO app.This module is mounted on the back of the remote controller of the Phantom 3 Professional/Advanced or Phantom 4.It includes a Mini-HDMI output port, Micro-USB port, USB port and a CAN expansion port.