My E39 530 came with an Xtrons PX5 Android radio installed. While I’m all about originality (and thus got the original head unit, too), I actually enjoy the features that this radio provides: Bluetooth audio streaming, hands-free kit, and a reversing camera. The downsides are that, by default, there’s no offline navigation possibility (only Google Maps is installed), and that you lose the option to set onboard computer-controlled values like the current time. Luckily, there’s a solution for this: the i-busapp. Not only does it replace the onboard computer, it also provides a live view of certain engine/car parameters, and can even be used for some basic coding.
Use of the app requires a USB i-bus interface. The recommended way of installing this is by hooking it up to the quadlock adapter of the radio. Slight problem in my case: Since my car originally came with the Navigation Professional unit, the quadlock adapter is in the trunk. The only suitable plugs are the white and blue plugs for hooking up the monitor. So even though this isn’t a recommended way of connecting the interface, I had to go this route. I ordered three suitable pins (BMW part no 61131383672, my dealer charged me for three even though they come in a set of ten), attached them to the interface wires, covered them in heatshrink, and plugged them into the proper pins (2 = ground/brown, 6 = i-bus/white, 7 = 12v/red). So far, things seem to be working fine!