Currently available on the iPhone and soon to be released for other smart phones is the FBI App to assist parents should their child go missing. the App will help parents quickly share information to law enforcement as soon as their child goes missing.
The App stores information like Name. Birth date, Address, Guardian Info, Phone Numbers of Guardians, Child's height, weight, hair and eye color, ethnicity, identifying characteristics and a photo of the child.
The app also includes tips for parents as what to do in the first critical hours after a child goes missing.
Some people are concerned about security. Is the server the information being transferred to secure? Another main concern is that if you loose your phone not only is your information insecure but your child's information is now insecure and possibly in the hands of someone else.
All in All from what i have read parents are mostly in favor of the app.