@eskimo - You rule. Honestly, we're struggling with wrapping our heads around how to think about this, so I really sincerely appreciate you taking the time to respond to us and doubly appreciate you being willing to investigate.
The R framework(s) are available via https://mac.r-project.org/ . There are separate Intel and ARM versions
Intel 4.1 - https://mac.r-project.org/high-sierra/R-4.1-branch/R-4.1-branch.pkg
ARM 4.1 - https://mac.r-project.org/big-sur/R-4.1-branch/R-4.1-branch.pkg
Our audience (medical/biomedical informatics researchers, primarily) tend do want to use their own versions of R with their own packages, etc. installed, so as a result we do not distribute R directly with our app (https://sites.northwestern.edu/stattag/). Instead, we link on build to "Current" and our app links to the R distribution on the user's machine at runtime. Our focus is on reproducible research, so the rationale here is that we want to allow users to govern the specific application (R, Stata, etc.) versions for their project. There are some other challenges with that, but our big question right now is how to approach ARM vs. Intel.
I think that means we have three scenarios:
Universal app runs on Intel machine with Intel R
Universal app runs on ARM machine with Intel R (I had previously tested this on the DTK before there was an ARM R and it worked fine)
Universal app runs on ARM machine with ARM R
Now that there's the possibility a user could have an ARM machine with either an Intel or an ARM build of R set as "Current," I'm not even sure how to think about this problem.
We're in the process of getting an ARM Mac Mini (we two developers both have Intel machines right now) and we hope to be able to do more extensive testing soon.
Any insights / ideas / critiques are very, very welcome.
Again, thank you
Eric (and Luke, Leah, and Abi)