The smart switches are getting much smaller these days. This mini switch from Sonoff (on ebay) can effectively be inserted into any switch.
Questions:
(1) Is it legal to be installed in Australia?
(2) If it's legal, does it need to be installed by a certified electrician?
Thanks!
/WT
Possibly, but not by you. You would need a licensed electrician and the product would need to have some sort of Australian standard compliance (c-tick or RCM??)