The Apple app store is certainly a disruptive market place which has changed the way mobile applications are developed and delivered. Apple has lowered the barrier to entry when it comes to creating mobile applications and though Apple will take 30% of your total sales, they will provide the sales, billing, distribution and development platforms. This has allowed developers to concentrate on what they love/do best, writing code without having to worry about marketing, distribution and setting up payment gateways.

But how much are iphone developers making?

Here are some links to some articles for a few applications which have made iphone developers a nice tidy profit.

Trism
Steve Demeter developed the iPhone puzzle game Trism as a side project, but now he's quitting his day job. Why? Because he says he's generated $250,000 in profits since he started selling the $4.99 game on iTunes this summer.
read more - http://www.demiforce.com/games.html

iFart
iFart is fast becoming one of the most popular iPhone/iPod Touch applications out there. The developer of iFart, Joel Comm, has been pretty forthcoming with sales figures, and on his blog he noted that over Christmas Eve and Christmas day, more than 58,000 people purchased a copy of iFart, netting him over $40,000 dollars in just two days.
read more - http://ifartmobile.com/

2across
Eliza Block, who's now earning an unexpected $2,000 a day from her crossword puzzle app, 2Across. Noteworthy certainly, but also instructive about the platform Apple has created for what can certainly be called "self publishing"
read more - http://www.instantcocoa.com/products/2across/

ISTEAM
Simple brilliance that a few 22 year old kids create an entertainment application for the iPhone that is so simple yet so brilliant it is already one of the most popular applications on iTunes and has netted the kids over $100,000 in just one month with over a million downloads.
read more - http://isteam.co.uk/

ISHOOT
"iShoot Lite" went live on January 3, 2009. Less than ten days later on January 11, the original iShoot rocketed out of obscurity as the number one Top Paid App in the iTunes App Store with 16,972 downloads in one day. It virtually blasted the reigning number one iFart app off its perch overnight. iShoot simultaneously grabbed the Top Free App number one spot as well.

For an app to reach number one and remain there, some 10,000 plus downloads per day are required. That's roughly $21,000 a day for this $2.99 app after Apple takes its 30-percent stake. Nicholas attributes iShoot’s meteoric rise to the release of his ‘Lite’ version, giving millions a free chance to experience the thrill of launching tank artillery. It’s important to note that a $2.99 price point was no barrier to the ultimate success of iShoot.
read more - http://ishoot.en.softonic.com/iphone

iPod Monkey Ball
Sega and Apple has squashed any doubts over the iPhone's viability as a platform to make games for - the two have revealed that over 300,000 people have bought the Monkey Ball game for the device in just 20 days.

At $9.99 a pop, that works out to $3m revenue in less than a month - figures which legitimise the iPhone as a development platform, Sega's US boss says.

read more - http://www2.sega.com/gamesite/supermonkeyball2/minigame/

iRetroPhone
iRetroPhone presented their Apple iPhone application last night at the NY Tech gathering. The iRetroPhone application is simple - it takes your iPhone and allows you to dial phone numbers using an old "rotary" phone - the type used on television shows Three's Company and MASH. CEO Gavi Narra noted that in the first day of sales, they sold 15,000 copies at $2.99 and the net revenue was just over $30,000. The iRetroPhone app took 1 day to build.
read more - http://www.appsafari.com/phone/8136/iretrophone/