It's all fun and iPhone games until Daddy gets a big bill. Garen Meguerian, a Pennsylvania father of two, has filed a class-action suit against Apple, claiming that the computer giant's App Store makes it all too easy for kids to charge things to their parents' credit cards without realizing they are spending real money. Here, a brief guide to the suit:

What is Meguerian's issue, exactly?
Meguerian let his two daughters, ages 12 and 9, download a number of free iPhone games like "Zombie Cafe" and "Treasure Story." The games themselves didn't cost a thing, but in the course of playing them, his daughters spent about $200, automatically charged to his credit card, buying virtual items like "Zombie Toxin," "Gems," and "City Cash." "These games are highly addictive, designed deliberately so, and tend to compel children playing them to purchase large quantities of Game Currency, amounting to as much as $100 per purchase or more," the complaint reads.

But I thought Apple already addressed this?
They did, sorta. As the lawsuit notes, with its latest operating system, iOS 4.3 (released in March), Apple now requires users to enter their iTunes password for in-app purchases, but Meguerian doesn't believe that's enough. He says that under the old policy, Apple was able to "pocket millions of dollars" in unauthorized "Game Currency" purchases. And, he says the new password policy isn't sufficient, since kids might know their parents' password.

Has Apple really pocketed millions?
It's unclear where Meguerian got that figure.

What does his complaint seek?
Damages and attorneys' fees for himself and all other consumers who were affected.

Have people taken issue with this before?
Yes. In February, The Washington Post reported on an 8-year-old girl who racked up $1,400 in purchases decorating her mushroom house in the popular "Smurf's Village" game. "The app preyed on children," the girl's mother said. Another second-grade girl racked up $150 purchasing buckets of stars and snowflakes in the "Tap Zoo" game. Apple made one-time reimbursements in both instances. In February, the Federal Trade Commission investigated Apple's in-app purchases, leading, in part, to the new password system.

What has the reaction to the suit been?
Some are baffled by Maguerian's finger pointing."Honestly, I'm not sure what he expects Apple to do," says Jared Newman at PCWorld. Since Apple started allowing in-app purchases in 2009, parents have the option to restrict it via parental controls and additional passwords. "At a certain point, the parent has to take some responsibility."

How popular are these games?
Very. And they're profitable. According to a December 2010 report, 34 percent of the revenue from the top 100 apps came from free apps with in-app purchasing. And, says Amy Lee at The Huffington Post, this "suit comes at a time where the profitability of such virtual games seems poised to explode."

Sources: Apple Insider, Mac Observer, Washington Post, PCWorld, InformationWeek, Huffington Post