To give you an example, if you have just bought an app – say a car racing game - from the iTunes Store at the request of your child, she can easily buy any other game /app from the App store in the next 5-10 minutes without even knowing your Apple ID or password.
The one-click purchase option available in your iPad or iPhone makes it convenient for you to buy new apps from the iTunes App Store with a single tap but at the same time, if you have kids at home, the one-click option can spike your iTunes bill as well.
