* it's FREE
Some parents may not be able to pay for the app. I don't want their child to cry because of that.

* Starts quickly
When your child is crying, you don't want to spend 20seconds tapping on your phone, do you?

* works in air plain mode
If you leave your phone or tablet next to your child, you probably don't want to crump your child with any radio signal

* battery efficient
This is obvious goal. This app consume almost zero energy.
*Lightweight and easy to use
We do highly recommend not putting the phone closer to the baby than necessary.