当然一旦上了BBS就不太能够专利了。那就当贡献了，为了整个人类的幸福。
It would be VERY easy for iOS, Android and WP7.5/8 to add one feature that limit the apps based on the pass code input. For example kids' pass code has relatively less game Apps and more educational ones.
Or two adults' pass codes pull up different apps.
The Apps can be a total set or different sets. The total-sub sets would be easier to achieve.
This will enables master and slave codes on iOS devices, just as if for PC account.
Simple, right?