Ah. I had blindly assumed when I flipped through the manuals that the pod could activate a new G6 sensor, but in fact the quick start guide says nothing about starting the G6 - just that you have to refer to the G6 documentation. The user manual states this, from page 272:
Caution: You cannot use the Dexcom G6 receiver with the Omnipod 5 System because the Omnipod 5 System is compatible only with the G6 app on a smartphone.
This has been discussed before in other threads (search for “receiver”); the G6 has two communication channels (referred to in the threads as “slots”), one dedicated to the Dexcom receiver and, now, the O5 pod, the other open for use by software apps including the Dexcom app. So now I understand why Insulet had to take over the receiver slot; they needed to leave the app slot open so that everything could be implemented on a smartphone. On a smartphone the Dexcom app uses the app slot and the app is required to activate a new sensor.
Some more selected quotes from the manual:
Note: All sensor and transmitter-specific actions and alerts are controlled through your Dexcom G6 app. See your Dexcom G6 CGM System User Guide for additional information.
Note: The Dexcom G6 app and Omnipod 5 App do not directly communicate with each other. They have their own separate communication channels to acquire CGM values. As a result, you may notice that, at times, the CGM values may slightly differ in each app.
Translation: the Dexcom app talks to the G6 transmitter using the “app” slot, the O5 app talks to the O5 pod using it’s own independent communication channel and the O5 pod talks to the G6 transmitter using the “receiver” slot. So the Dexcom receiver doesn’t get any BG values after the Dash pod has taken over.
There are extensive discussions in the other thread about using the receiver, starting here. There is no way of connecting the receiver to the transmitter once the O5 pod is connected because it is the pod which takes the receiver slot and the pod cannot be turned off!
So, yes. I can see now that your original statement is correct, at least in official terms:
But that’s not the only way of activating and controlling a G6 sensor from a smartphone and, because the smartphone implementations use the “app” slot any will work:
- The official solution seems to be to buy a compatible smartphone. I did that when I was considering the O5 (I bought a Samsung SMG973U (an “S10”) for a little over USD200, they’re selling for USD180 or thereabouts now. I didn’t end up with the O5 but the phone works fine for AndroidAPS.
- The certainly unofficial approach with an existing Android phone is to use the BYODA web page to obtain a hacked version of the Dexcom app compatible with the existing phone. The page has a lot of different versions and, while the Google store may refuse to install the current Dexcom app, other people have used BYODA to install older (I assume) versions on “incompatible” phones.
- A more supported approach is to install xDrip+ and not use the Dexcom app at all. I tried this initially but couldn’t get it to work. I believe this is because I was, at the time, running the Dexcom app on my old phone (an iPhone XR) so this has consumed the “app” slot. xDrip+ has a much much better interface than the Dexcom app including somewhat more sophisticated alarm control.
You can try (2) and (3) without interfering with your current setup and without committing to the O5; with the Dexcom support on your 'phone you can use the controller for the O5 if you want to transition to it.