Arizona uses MyIRMobile, as mentioned in the article. I was an early adopter and signed up as soon as I could after getting my 2nd Moderna shot last March.
I got my booster on October 29th and recently downloaded the QR code for all 3 to my phone and tablet. All you get with that is the code.
I also printed a copy. The printed version is a bit bigger than the CDC card and includes the details of the QR code printed out as well as the code itself. At the top left, above the code, it says SMART Health Card. The line below that says COVID-19 VACCINATION.
In the top right corner on the right side of the code, it says As of, with the date I printed it. Below that and directly to the right of the code is my name and my DOB ( date of birth). Following that are each of my doses with the dates I got them, and the Manufacturer / Lot Number for each.
I've been carrying that with me, along with my CDC card. If I need to get a 2nd booster due to my age and health before traveling in the summer, I'll go through the downloading and printing process again. Just like the first 3, a 4th shot will be automatically reported to the Arizona Department of Health Services. Frankly, I was pleasantly surprised that AZ started this so early.
The initial process has a bit of a learning curve, but all states should have the data. It's just a matter of making it available to us in some usable way.