In-app purchasing (IAP) can be a big headache for parents. It’s very easy to end up with your kid buying hundreds of pounds worth of princess hairdos, rainbow pixie dust, and pony food.

Apple has recently been getting flak for a lack of protection in this regard, but in fairness what else can they do? ISVs have found a way to realize revenues against enormous development costs in IAP. This system works for everyone in a broad sense. It just needs a little adjustment to stop people getting bill...