All these phone apps drives me nuts. Which is better than which and why? Why bother? I have dozens and dozens on my Android phone and most I know jack about.
I did just install one tonight that I guess makes sense, offered by my HMO: A covid-19 vaccination card on your phone. I ran out of lines for all my covid-19 vaxes on the card they initially gave me. How many times have I had to scan that card, both sides, then scale down the JPGs, print and cover with plastic tape and trim? And you know what? I've never once shown any of these to anybody!
Now, if asked, I can fire up the app and show my shots. I don't think they show the batch numbers of the shots but do show Moderna and the dates.