Smart phones like Apple's iPhone are permitting children to gain access to violent and sexually explicit games.
The classification loophole means schoolchildren given smart phones and similar devices by their parents are being exposed to material which would be restricted in other forms of media, such as video game consoles, magazines and movies.
The material can be downloaded on to iPhones from Apple's App Store in as little as 60 seconds, and only a credit card or debit card is needed to create an iTunes account to download the apps.
An example of such games is the '5 Minutes to Kill (Yourself)' game, which has an image of a man with a knife through his head as a logo, and where players have the option of a number of weapons to "get the job done".
Another is the 'Girls And Drinks' game where players are encouraged to drink excessively to attract "sexy" barmaids, with a spiel saying, "Choose a sexy bartender. The more you drink, the sexier she gets".
The suicide game triggered a furious response from Beyond Blue chairman and anti-depression advocate Jeff Kennett.
"Put this in the hands of a kid who is depressed or has been bullied, it's like throwing fuel on the fire to the problem," News.com.au quoted him as saying.
Apple has about 150,000 apps available on its site in Australia, and the ratings it gives are in small print on the games' listings.
The games do not contain ratings from the Government's Classification Board, as they are required to under Federal law.
The board's website notes "games must be classified by the board before they can be sold or hired in Australia".
A spokeswoman for the Federal Attorney-General's Department said it was "considering the issue of mobile phone applications".
An Apple spokeswoman said the company "self-rated" a number of the game apps on its site.
"Our approval process is about protection of consumer privacy, protecting children where we can," she added.