Comment by robohoe

Heck you can even cobble stuff together with Home Assistants and various door/window/presence/water/humidity sensors. I was able to build a notification system when doors, windows, or fence gates are open. Same with panic buttons that alert my SO if any of us need assistance when putting kids to bed without whipping out the phones.

All of that can be loaded into HASS using a $26 Sonoff Zigbee dongle and various Zigbee devices like Aqara and others.