Okay then, what if apple had an app that shows a list of temporary apps in the area, and you can choose which to use or even to download the app?
If you go to the App Store and click on "Near Me", you can often find apps related to where you are. (i.e. if you do it in a BART station, you'll see BART apps and if you are just in Berkeley itself you'll get SpoonRocket (which started in Berkeley), several AC Transit apps, and BerkeleySide.)