Best of luck! Please report any progress you have made. I threw in the towel last year...
Some info which might be useful:
At least for the iPhone, there are two useful (...) apps, the Porsche Connect and the Porsche Car Connect. I subscribe to both and pay the Infotainment and Navigation ransom (at least for another year).
What do I get?
Porsche Connect gives me a very convoluted way to achieve Voice Commands for Navigation. I don't have the Voice Module.
I can have Siri, or Google Assistant bring up Porsche Connect. I then have to press the Search input line to get a keyboard and press the microphone symbol for a Voice Input. Assuming that it found what I want, I then have to touch the Star symbol to save the destination in the Favorite POIs (Points of Interest).
I then have to press the NAV button on the infotainment, bring up the maps, press the screen and use the right radio control to navigate to the Phone's POIs, select it, and then scroll down (hopefully is the first) to get the destination selected. You either need a Navigator, or you will kill yourself due to inattention to where you are going.
Porsche expects you to get off the road to accomplish this feat... Voice Controls is not the Porsche way...
The Porsche Car Connect is a separate pay service provided by Vodafone. It accesses your car via the Data SIM card (I have a T-mobile card rather than the Porsche ATT, I'll get back to that). It can tell you the present mileage, the ignition status, the amount of fuel you have left, the range, can find your car on the map, can do a whole bunch of operations (horn, lights etc) which I haven't tried because I didn't want to scare anybody in the garage I was using for parking.
The feature I like a lot (and used always) is the Geo-Fencing. You set a Geo-Fence perimeter and you get notified every time the car gets in and out of the fenced area. So you know if the parking attendant is having Ferris Buehler's day off with your Porsche, you know where he is at present (it shows on the map) and you can guide the police to the Porsche with the flashing lights and the screaming horn. I wish the notification was a bit louder though...
Back to the SIM card. The car has one embedded in the Infotainment system. My experience is that it is slow. It also does not allow any other phones/tablets/computers to connect to the onboard Porsche WLAN. Porsche offers for just over $100 to give you an ATT card with limited (but adequate) data and connectivity via WiFi for a few more devices. For my own reasons, I got T-Mobile to give me a card for about the same price (it takes the big 1/2" cards). My wife can happily connect to the Internet and book hotel rooms, facials etc while I am having a good time in the twisties. You can use your phone as a hot-spot (I tried it and it works, but I couldn't be bothered.
CarPlay not only does not use Bluetooth, it will rudely disconnect any other phones/tablets/computers using BT for whatever reason. I tried and discarded the option of using an old iPhone for this reason. I would lose the BT connectivity for my main phone.
So I threw in the towel and got an iPhone8, which I hate and will hate for eternity. I run Linux at home... &^%$^$pple...
Last ditch possibility.
If you are looking at a Used/CPO Porsche, you might as well forget an Android compatible PCM. If it ever happens, the transition/conversion will be excruciatingly expensive (like buying a new PCM unit for a few thousand or re chipping the existing PCM for a few hundred and another few hundred in labor.
The one thing I haven't experimented with is having a tablet doing screen mirroring in WiFi with the Smartphone in my pocket. I could then run Android Auto (?) or the apps directly (?) with the Smartphone Google Assistant/Voice commands. If anyone gets decent operability, please report.
Good luck
