> This is in Europe, mobile data coverage is practically 100%, isn't it? Not really. In tunnels and remote areas (I mean middle of nowhere train tracks with fi

> This is in Europe, mobile data coverage is practically 100%, isn't it? Not really. In tunnels and remote areas (I mean middle of nowhere train tracks with fields, hills, cows as the only things within a multi-km radius) coverage can be extremely spotty. Even on very highly used high speed routes like Paris-Lyon or commuter routes like Paris - Melun there are blind spots (and big ones depending on the provider).