I came across this gadget on ebay which claims to be able to turn the (I think) NGT 4.5 on my 2011 W204 estate into a carplay compatible device, I contacting them ref instructions and got a prompt reply back from them with a link to their instruction page - Mercedes-Benz carplay box

I also found a UK based company that claims the same from a similar device (You searched for w204 - Unique Auto Developments) but at a much higher price.
My question is has anybody fitted either of these and are they worth it or a pain to use ?

I also found a UK based company that claims the same from a similar device (You searched for w204 - Unique Auto Developments) but at a much higher price.
My question is has anybody fitted either of these and are they worth it or a pain to use ?