4. Don't share your password or credit card number. Nowadays, many kids are tech-savvy enough to place an online order or use a credit card for in-game purchases, so Simone de Rochefort, contributing writer and editor at pixelkin.org, a resource for gamer families, warns against sharing credit card numbers or passwords with your kids. "It doesn't equate to not trusting them," she says. "Keeping a password private is about safety." Some games, apps or websites store credit card information, though, so this method isn't fail-safe.
[Read: How to Make More Secure Passwords.]
5. Help kids make the connection between virtual currency and real money. Use in-game charges as a way to teach kids about financial decision-making. Virtual currencies in a game often don't feel like money, but using something tangible to represent that virtual currency can help kids understand the old adage that "money doesn't grow on trees." De Rochefort suggests keeping a cache of chocolate or a stack of quarters and subtracting one for each in-game purchase. "As soon as a kid is old enough to have an allowance, give that physical representation," she says. "Relate it to things that they love or an activity they'd like to do."
6. Set up alerts for in-game or in-app purchases. Getting email alerts for these transactions could help you address kids' spending habits before they become an expensive problem. Of course, adults can get caught up in mobile games too, de Rochefort says. If you play mobile games yourself, alerts could also help ensure that your own FarmVille or Candy Crush addiction doesn't empty your bank account.