I bought iris contact sensors from lows and installed on my patio door and front door. I would like to get notification on android app and on sms when somebody open the door while I am ARMED (AWAY) or night time (any status). I am new to this smartthings worlds and I appreciate if somebody can guide me with step by step instructions.
Thanks.
Welcome! 
The first part is exactly the example given in the official knowledgebase article on smart home monitor, so you can go ahead and set that up.
As far as doing it at night, how are you defining ânightâ?
Do you mean âafter sunset and before sunriseâ?
Do you mean a specific time frame, like â10 PM until 8 AMâ?
Do you mean when your house is in ânightâ mode?
Or something else?
Also, before we go any further, read the following to explain the difference between âModeâ and âsmart home monitor armed stateâ because it can help clear up a lot of confusion.
As far as doing it at night, how are you defining ânightâ?
Do you mean âafter sunset and before sunriseâ?
Do you mean a specific time frame, like â10 PM until 8 AMâ?
Do you mean when your house is in ânightâ mode?
Yes
Thanks for all informative links, I will go through it.
Welcome - one more thing to understand (coming from being brand new about 30 days ago, so I had to learn everything like youâre doing right now) is that some tasks are done with the built in SmartThings app and somethings are done with apps that are âadd-onâsâ to the SmartThing App. So for what youâre trying to do, there is SmartHome Monitor, which is the first button in the Android app on the bottom left. It will do what you need. But there are other âappsâ that can accomplish this too and usually, they have more flexibility and options.
For example, when i started, I used the built in ST (SmartThings) âRoutinesâ (called Automations) to control my lights. But I quickly found that it didnât give me the options I needed so I installed an add-on app call SmartLighting, which is still part of ST but an add on. It has way more control. As JD suggest, read the FAQs and if youâre still lost, reach out to the community here. Iâve found them to be extremely helpful.
Thanks for the tip 
Any recommendation on add-on for my purpose?
Well, that depends on what you have installed. If you have lights (and of course everyone in the world should have smart lights :), I would recommend SmartLighting to Start. Here is a sampling of mine.
As of now I have only contact sensors.
I use contact sensors to know when things open or close. I use motion sensors to turn on/off lights, notify me when someones at my door. The only time i want a text is if my garage door opens. I used to have this setup if my front door opened but my kid runs in and out all day long so I was getting dozens of useless texts.
This should be of interest. (This is a clickable link.)
