The most reliable type of movement sensing product is the mattress pad option. This product is placed under the mattress, usually on a hard board and will only work with some types of mattresses. This unit relays messages to a nursery device that alerts parents on a parent device or with an alarm in the nursery (model dependent). The BabySense 7 is a good example of a sensor pad that works under your baby's mattress.
But these nursery essentials can be as fussy as the babies they keep tabs on. And like virtually every other household appliance, they are growing increasingly more capable and complex. In addition to conventional video baby monitors that use a camera and a handheld LCD display, often called a “parent unit,” there are now also Wi-Fi-enabled systems that connect to your home network and use your smartphone as both the display and the controller, much like DIY home security cameras. These latter models offer high-defition video, intelligent alerts, and the ability to check on your child from anywhere you have an internet connection.
Wireless encryption: This ensures that no one else can tap into your monitor’s “feed” and see what’s going on in your house. WiFi-enabled monitors are great for portability and range, but may be more susceptible to hacking. If you go this route, be sure to secure your home wireless network and keep the monitor’s firmware updated. Otherwise look for digital monitors with a 2.4 GHz FHSS wireless transmission.