Got this from the website but I'm still unsure how it works.. do you download the files to a USB from somewhere or does it connect to the internet via your phone?
"You can perform this software update yourself. To do so, all you need is a standard USB memory stick with sufficient memory capacity. If required, your BMW Dealer will also have a USB memory stick for you to purchase. To perform this software update, you will require the USB audio interface (included in optional equipment codes 6FL, 6NH, 6NK or 6NL) as well as the Control Display and iDrive. Your vehicle can be updated provided that you have the ‘Software update’ option on your ‘Settings’ menu in the Control Display.
The software update your vehicle requires depends on the equipment in the vehicle. Please enter the last seven digits of the Vehicle Identification Number to select the software updates available for your BMW. "