When I open the FlightAware app in-flight with no wi-fi, I want to see the most recent info, could be old, about when the plane will land. Instead, I get a blank page complaining about no internet. Sigh.
Just show the last known data while looking for a connection. Put up a popup that I can dismiss that says there is no connection. Maybe flag the data as stale, if you really want. But let me see the data for my flight.