All:

After much reading, I decided I'm going to upgrade the 2015 GL 550 to a new Android-based headunit. I understand the limitations as I've had something similar on another vehicle. No native Sirius/XM. But you can download the app from the Google Play store on the device and stream your stations that way. Most functionality will require Internet connectivity in your vehicle (mainly for apps) but the plus side is you can watch Netflix, Prime, Hulu, etc., even while moving (not that I would). I keep a hotspot online in my GL for the kids anyway. I also understand you need an adapter to get good FM radio reception ($15). The biggest thing for me is getting Google Maps. For my S550 Coupe I'm just going to get the GTACARKIT Apple CarPlay/Android Auto module which uses factory headunit and replacement cigarette tray to retrofit wireless charging.

Headunit:

Wireless Charger (replaces the little cubby).

Keep you all posted.

 

** UPDATE**
Decided to go with this wireless charger instead:
I also installed something called Headunit Reloaded that replaces the default Zlink (trash) Android Auto & Carplay. Now bluetooth calls and Google Assistant work properly! I can also now use the Android Auto dialer to select contacts. So I'm pretty happy now.


Headunit installed. Smooth install I must say. But I watched enough videos beforehand from various sources that it made things a lot easier. The instructions were 80% there. The random YouTube videos got me to 100%

Pros:
Modern looking touchscreen with color.
Plug and play install.
Can watch anything you can download in the Google Playstore while driving or stationary.
Split screen view is useful when navigating or something anything else.
360 camera works like factory. Essentially it just kicks you to the factory NTG 360 camera.
I like how easy it is to switch back and forth between NTG factory and new headunit display. Both are shown using the same new screen.
All buttons in the car continue to function as expected.
Uses factory mic and speakers

Cons:
No FM radio tuner. I felt mislead on that.
No SirusXM tuner. That's OK, because the streaming app works fine and allowed me to remove one car from my subscription.
Default skin is trash. I downloaded a better skin. It's called Agama Launcher (ugly name, nice skin).
Because they essentially stuck Android on a tablet like screen, not all apps have big enough buttons. So sometimes you need laser precision to push an on screen button while driving. Definitely more distracting.
Unable to get Google Assistant working to call people. It works for weather, etc. -FIXED. Downloaded Headunit reloaded and when using Android auto this is resolved.
Dialer is basic as hell. No favorites, only scroll, or search. Not easy to do while driving. -FIXED. Downloaded Headunit reloaded for Android Auto and now I can use the contacts/dialer from the Android auto screen. Also reads out my messages (Teams, and text messages).

So I can tell you this won’t be for everyone. For me, my SUV is driven one week on, one week off usually when I have my kids. It’s also for road trips so I like the added functionality.

If I had a newer GL/S I would stick with factory. But I have a 2015 with over 100K miles so it is an upgrade over the tiny damn near black and white screen that comes factory.

 

That is great, looks like the newer ones. I still prefer the more integrated look of the screen being built into the dash more, I know many mfrs are putting them like this. Same as you, I only use the car occasionally, so I dont really care one way or the other. Great job,

 

I'm with you I tend to hate ones that stick out like it was an after thought. I love the smooth integration. But this is my "beater" albeit a nice beater. So I wasn't sweating it.

 

Thank you for sharing. So for the unit to use existing speakers and mic - do you connect your phone to MB Bluetooth?
Also, does your car have Harman Kardon audio - I'm curious if that would add any complexity to the installation.

 

I don't believe I have any special speaker setup. I think it's MB factory. If anything they may be Bose but I don't recall seeing any labels.
That said in the settings of the new headunit there is an option to change the speaker setup to factory, Harmon or Bose.

What I can tell you is it uses the same mic and speakers. Bluetooth can connect to either your headunit (Android) or Mercedes. Because I use a Hotspot in my truck anyway I connect to the BT in the new Android headunit. But I must warn you the BT stack and phone app is trash. The dialer is super basic. No favorites, only search by typing and no voice dialing.

That part truly sucks. But it works.

 

Looks good