I don't know if it possible. I know that a scanned QR code can be used to open Safari, but I don't know if any other app can be opened. To be honest, probably not, as Apple's security protocols prevent apps from accessing other apps. However, that's not to say it can't be done (I'm not an iOS programmer).
I'm man]inly posting to ask you to refrain from continually posting this same question. Making more than one thread on an issue fragments the conversation and makes it hard to follow. Not only that - it's against this forum's rules to make duplicate threads.
So, I've deleted the other two threads that you've made about this question. Please keep any/all follow up questions and discussions to this thread only; do not start another. Thanks for your understanding.
Marilyn