Yeah, so advance.
But on the other hand, if suay suay kena power failure, all electronic devices fail to operate.
U kena trapped or locked up in the shop cannot go out.
Dinner time, no sign of u, g/f calls, wife calls, mum calls, siao liao la.
Unless the electronic devices are battery operated but then again, if suay suay kena battery flat, oso siao liao la
..