As long as the mobile internet works it's possible.
replyIf we're talking about a situation where the grid goes down, the mobile internet is most definitely not working.
Surprisingly mobile networks seemed to stay up in Portugal. I'm not sure to what extent and if they lasted for the whole duration of the blackout.
They definitely limited consumer use though.
replyI love in Spain and in my zone I didn't have Internet access until after 22:00, and it was sloppy at best.
reply0:49 and light came back, and woke us for a moment.
So yeah, you need local first POS applications.