Apple has banned That Nguyen, the popular app developer, from iTunes and the Apple App Store, after it was discovered he hacked 400 iTunes accounts, and used them to boost sales of his comic book apps.
The company also said it has now tightened security, and similar situations will not occur again.
Nguyen had, at his peak, 42 of the top 50 book apps in the market.
All apps have now been removed and the developer banned due to violations of the "developer Program License Agreement including fraudulent purchase patterns".
Apple also recommended that users with compromised accounts should contact their banks and change their passwords.
As part of strengthening their security, iTunes users will likely be asked to enter their credit card security code more often when making purchases.
Nguyen had, at his peak, 42 of the top 50 book apps in the market.
All apps have now been removed and the developer banned due to violations of the "developer Program License Agreement including fraudulent purchase patterns".
Apple also recommended that users with compromised accounts should contact their banks and change their passwords.
As part of strengthening their security, iTunes users will likely be asked to enter their credit card security code more often when making purchases.
