I use SmartThings for security for over a year an a half. First thing you need to understand is the SmartThings has some reliability issues but it has greatly improved over the past 8 months. With that said, I would say that it isn’t as reliable as a dedicated security system. SmartThings sometimes sends false alerts, such as false motion or reporting a door opening when it didn’t. Unless you have the ability to bring up remote video so you can see what is going on then don’t use SmartThings for security. Not being able to determine are real break in vs a false alarm will get really old after the first time it happens.
SmartThing as well as professional security systems both need a connection to the outside world. My hub connected to a battery backup connected to the cellular network. That way even if the thieves cut the power, phone and cable lines the hub stays active. For extra security I have the hub report if there is a power outage. BTW, security camera need to be on backup power and capable of connecting through the same internet connection.
If I get an alert on my phone that something is wrong my first step is to bring up the cameras. If I see that there is a break in in progress I call the police. If my cameras are down or have been tampered with, I call the police.
I DO NOT SOUND ANY ALARMS. I don’t want to scare them away, I want the police to catch them. If they are going through the house stealing things like TVs then it is going to take them a few minutes which is plenty enough time for police response.
The other benefit to using SmartThing is you will be alerted quickly enough to take action. With many professional security companies the alarms take upwards to a minute before the equipment even calls the security company to report a break in. Then it takes even more time for them to call the police. Keep in mind that in almost all cases when police are sent to check out an alarm they instinctively assume it will be a false alarm, because it usually it is. If you personally called the police and can confirm your house is being broken into and you tell them you can see it happening on camera that will change how the police respond because they know its for real.
In closing SmartThings has great potential but it isn’t quite there yet but if you follow some of this advise you will be further on your way to a more secure home.