"Apple's in-app purchases have come under criticism. Critics say app developers are luring children to buy virtual goods at outrageous prices.

Another common complaint is that some purchases are priced at $99.99, in an attempt to trick users into thinking the fee is actually 99 cents.

Some children have racked up bills as high as US$1,400. This has outraged parents and prompted an FTC investigation.

One focus of inquiry is a 15-minute window that allows unlimited in-app purchases after a parent has supplied their password to iTunes.

In the meantime, parents will need to be more cautious when giving their children access to iTunes content."