I wonder what Facebook will say when the governments of the world realise they can use this capability to contact their own citizens - especially if Facebook's continued operation in that country is contingent on its cooperation. 'Safety Check' is just the end user experience; the underlying mechanism is a way to propagate messages invasively across a geo-social network. Like any technology, 'good' or 'nasty' depends…
Usually this is enforced at the cellphone carrier level. The US has the amber alert protocol which also has a function for the president to dispatch any message (and can only be used by the president iirc), and that level of message can't be turned off via settings. Even in our best countries FB usage is never 100%, so cellphone / landlines makes a bit more sense.
Re: How Facebook's Safety Check Works
#51I suppose I hadn't really thought about why they'd use Facebook when you can just message all the cellphones in a geographic area. Your reasoning makes sense.