Brandon Cowan is a boy genius and founder of Crazy Dog Apps. At just eighteen years of age he has three apps in the top 100 downloads, and now he's helping you do it too - for under $5.

"I've made an app on how to make an app. App Making Guide is really for anyone. It'll take you from idea to app store and everything in between," Cowan said.

He may have just left school and still lives at home, but the app world is Cowan's oyster. He says that it all starts with a simple idea.

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"When people have app ideas I've noticed that they don't know what to do with their idea. They're got a really great idea but they don't know how to turn it into a reality. If they call up an app development company, they'll be quoted thousands and thousands of dollars, and most people don't have that," he said.

Seamus Byrne from CNET warns that "not every app will make a fortune, and it's such a roll of the dice right now."

He says to be wary before investing big, because half of all apps are never downloaded. Byrne says the key to making it big is to create something simple, that answers a question.

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"When it comes to any app, you have to solve somebody's problem - and that might be boredom," he said.

"Whether it's in the kitchen, or in the car, or anywhere at all, if you can solve a problem that somebody else hasn't solved yet, then you've got a great chance of making big money in apps."

More stories from reporter David Eccleston

• Crazy Dog Apps - www.crazydogapps.com.au