For those you are interested in the X4 user guide and have already a VIN code of their car. Go on Apple store or Google Play store, download the free app "BMW Driver's Guide". Then enter your VIN code, and you should get the X4 user guide.
I typed "you should get", as my VIN code is not valid and match to a 316i produced in 1978!!!!!
Anyway in the main page of the app, the X4 is listed under the Driver's Guide.