Update: Manton Reece points out that the issue of in-app purchases being made without challenge is probably due to the App Store's holding onto purchase authentication for a few minutes after buying or updating an app. Craig Hockenberry cites the advantages and potential pitfalls of 'communal computing' on iDevices.
Several iPhone and iPad users have noticed charges totaling several hundred dollars on their iTunes accounts. At first, the issue looked to be part of the App Store's recent woes, but it appears to be linked to an app called Fishies from PlayMesh -- best known for its iFarm app.
Fishies allows you to create a virtual fish tank. You can raise fish, become friends with other users and make purchases for your underwater world. The program itself is cute and colorful, therefore appealing to kids. While the app itself is free, you have to purchase in-game currency called virtual pearls. These run from 99 cents for 10 pearls to $149.99 for 1950. To do this, you need to input your iTunes account information -- though some are reporting that the app isn't prompting for this before the purchase is made.