The language I found was:

> when the application is downloaded and launched

So it looks like the law only requires it on first launch. Which makes sense if the application can only be run from that one account. Apps that can be launched from multiple accounts are not singled out in the law, but the spirt of the law would have you checking what account is launching the app and are they in the correct age range.

That's not a guarantee. It's up to how the courts interpret that and. Given that this law is meant to handle a moving target like age, I fully expect them to interpret it as its disjunctive form.