In their nine months of existence, more than 1bn iPhone applications, commonly known as "apps", have been downloaded from Apple's online store. Many are useful tools to enhance everyday activities such as socialising, shopping, travelling and pretending you're a spy; software that does smart things you never thought possible.
But among Apple's list of the 20 bestselling apps "of all time" the biggest success story is iFart Mobile, which allows users to broadcast a flatulent parp in a variety of hilarious styles. Childish, yes, but it continues to earn the company behind it $10,000 a day. And iFart's business triumph has not only led to a plague of trumpeting copycats but also a craze for increasingly controversial apps that are more morally questionable than a Conservative MP with a moat. Here are some of the worst offenders:
Girlfriend Tracker Polygamists and cheating boyfriends are presumably the market for this "handy" tool that allows men to calculate the menstruation cycle of their partners so they can "decide how to plan your night".
Sound Grenade The bestseller in the "annoyance" genre of apps, it emits a high-pitched sound when opened that is designed to annoy and agitate anyone in your vicinity.
Baby Shaker Withdrawn after complaints to Apple, the game allowed players to silence a crying virtual baby by shaking their iPhone. If successful, two large red Xs appeared over the baby's eyes.
iSnort An unofficial app that, combined with a credit card and a crisp fiver, helps users simulate chopping and snorting cocaine.
I Am Rich A glowing ruby display you could download for $999. The app did nothing - except let people know that you had a grand to burn. Apple removed it after just eight sales.
Boom! BOOM! Shotgun Pro The French makers of this virtual handgun claim that it helps in the recreation of "childhood games of playing cops and robbers".
Swine Flu Tracker Keep updated on your current threat level with this free app that plots the latest outbreaks and scares.
Drunk Sniper Tilting the iPhone allows users to engage in an "amusing" simulation of being drunk and unable to pee without splashing the loo seat.
