how will users be informed if an app is not running on their current iOS version? Let's look at the following scenario:
an app is not supporting iOS 8 anymore. how would iOS8 users know they have to update in order to get the latest app version?
is a badge still visible on the appstore icon informing the user that there is a new version of the app and when clicking on "upgrade" he will be informed that this app is not supported with this OS-version or how does it work?
When vieweing the update in the App Store it will tell the user it requires iOS 9 or above.