A U.S. father learned the hard way why children shouldn't play with smartphones when his 14-month-old daughter used his iPhone to buy a car listed on the online auction site.

Luckily for Paul Stoute, of Oregon, the car in question was a classic 1962 Austin Healy Sprite in serious need of care and attention, meaning that his daughter's winning bid of just $202 plus delivery ($225 in total) didn't exactly break the bank.

According to Portland's KPTV, Stoute was already logged into his eBay app when toddler Sorella started playing with his phone -- something he admits she enjoys and that until now they haven't prevented her from doing.

However, the first he knew about taking possession of the car dubbed "Frankensprite" by its existing owner was when he received a sales confirmation email from eBay.

After thinking long and hard, the Stoutes have decided to keep the car and will fix it up in time for their daughter's 16th birthday. After all, Stoute senior had been following bids on old wrecks in need of some tender loving care, prior to his daughter's winning bid. However, judging from the state of the pictures posted of the car, it looks like every one of Paul Stoute's weekends, for the next 15 years are now spoken for.

And although this time the story has a happy ending, it is one of a growing number of reports that have hit the headlines this year about children running up huge bills on their parents' phones and tablets thanks to making in-app purchases. For example, in March, an eight-year-old British boy made the national news when he managed to run up an $1480 bill while playing a Simpsons iPad game.

So, how do you make sure that children can't run up bills making in-app purchase on an iPad or iPhone or that a classic British car isn't on the back of a flatbed trailer on its way to your doorstep? Follow these these two easy tips:

1. Turn on the passcode lock

This will lock the phone or tablet's screen and will require a pin number to activate the device. Go to Settings, then to general and turn the Passcode Lock on. Then in the auto lock menu select a time limit, say 2 minutes, for the automatic activation of the lock screen.

2. Increase usage restrictions

On the same menu page, select restrictions and choose another PIN code. Then scroll down to the Allowed Content section, and for absolute peace of mind, turn off In-App Purchases. However, there is also a setting which will prompt the user to enter a password before being able to make a purchase and that can be activated in the ‘Require Password' option. Just make sure it is set to "immediately". That way, as long as children don't know the PIN codes, the device should be safe for family use.

It should come as no surprise that since the Austin Healy incident, the Stoutes have activated the iPhone's lockscreen and have deleted all apps that can be used for making purchases.