This app I created gives kids (or adults) a simple interface for them to send a text message or to place a call to a contact. *The phone must have a phone plan to call and a text messaging plan to send a text.*
The app is very customizable!
Buttons can be customized with an icon and you can also customize the text message to send. There is a phone call button which instantly places a call to the contact. The phone number is used for both the text messages and the phone call.
The settings button is greyed out on the bottom-right, so kids cannot see it compared to the bright and colorful buttons. (parents can remember where it is at :) ) The password to reach the settings page is "parent".
I hope this helps you as much as it did for us!