Last Updated: 2021-05-16
Any "mission-critical" software — software where someone cannot do their job if it's down (e.g. medical stuff) — must be aware of internet connectivity.
Without this awareness, the user has no idea the network is the problem and cannot take action to improve their lot (e.g. finding better connectivity). Moreover, they are likely to blame you, the programmer, for issues instead of realizing it was their internet. From their perspective, the app just doesn't work.
Case in point:
When I developed a bar-code scanner for COVID tests, the default (unplanned) behavior was that it said "patient not found" when the application had no internet connectivity. In a sense this was true, but it wasn't specific enough. It could have said "no internet"
Communicate internet connectivity within applications