My Shiny app works perfectly on my PC and on my Mac. In fact, it's a fairly simple update of an app that I had earlier on Shinyapps.io.
- All packages are up-to-date,
- Previous version was archived (and then deleted to see if that made a difference)
- A new token accessed from my account in ShinyApps.io
- shiny package and rsconnect package reinstalled,
- Shiny app file is named "app.R", and all other *.R files removed from folder.