Here is another smart sensor that lets you monitor your home for any intrusion. Strips by Sensative is an ultrathin sensor that fits in your door or window & frame. It is weatherproof, so you can use it indoors or outside. It works with Fibaro, HomeSeer, SmartThings, and other hubs.
This magnetic sensor can sense when a window or door is opened or closed. Strips is under 3mm thin. It sends you alerts through your smartphone.