One of the great things about home automation is the possibility to activate scenes based on presence of people in the house. Having solid presence detection in your home is not easy to achieve. There are a lot of ways to do this, but most of them use ping your devices, using network connectivity, Bluetooth or GPS geo-fencing technology. These solutions might work for some use cases, but if your presence detection is based on devices will only work for known devices and people. Meaning you can never be 100% sure that no-one is home.
So do not, I repeat do not, trigger scenes that shut down all the lights if no-one is home based on phones. I’ve a great story about a baby sitter that called me very unhappy about all lights being turned off and also that every time she switched them on they went off again. This go back to one of the essential rules of home automation. Read the 7 tips for a successful home automation.
However, switching lights off when nobody is home or switching random lights on while you are on holiday are great benefits of home automation. This is something you want to achieve. A great way of doing this is by installing an alarm and read the status of the alarm, e.g. Fully Armed, partial armed or off.