@Wayne-TP 

Hi,

An SMS is not "drowned" in notifications when you have a lot of them and it disappears much less easily... 

The phone call is hard to miss (long ring, vibrate, if the sound is not muted yes )

For nighttime use (door/window opening detection, for example), this would be much better than a simple notification with a short beep. Or you could install a hub that rings next to the bed...
In France, almost all alarm systems make phone calls...

I know that Tapo products are not really designed to be an alarm system, but honestly, it works very well ! Product-wise, all that's missing is a keypad (but you can activate/deactivate it using your phone or a connected button). There's even geolocation in your app, it's great !  At this level you could even go further as Synology does by detecting entry/exit of the home with identified WiFi networks 

Thanks

Alternatively, a simpler option is to add a system to the Tapo app to make the phone/app ring (with the desired ringtone and volume) as a smart action until the alarm is deactivated (for example, with a button to deactivate with a swipe of the finger).

Phone calls are useful if, for example, you want a call to a landline number rather than a mobile phone. And, historically, in France, alarms made phone calls because at the time there wasn't a mobile data network everywhere...

Thanks.