If you're one of the million-plus people using a new 3GS iPhone, chances are at least one of the applications you've downloaded was dreamed up in Utah, where companies are coming up with everything from movie showtime programs to teaching tools and phone directories.

Apple's recently released iPhone 3GS sold more than 1 million nationally in its first three days, and the iPhone developers kit has been downloaded more than 100,000 times. Besides that, 50,000-plus applications are available in the Apple store, while more than 30,000 people actively work on creating more apps, among them a number of Utah companies and individuals.

Jason Izatt's Provo-based Izatt Inc. has made several apps and has more in the works. It also offers training courses. He's steadfast in his belief that if you make the right product, it could be huge, with many millions of devices worldwide able to run your application.

Izatt's iPhone apps include MileBug, a business-miles tracker; FingerSpell, which teaches American Sign Language; Bumps, which teaches Braille; and iRival programs for BYU or University of Utah fans.

Such diversity is not unusual. "Some companies build games, others follow a passion. Some run with their skill set," Izatt says.

About a third of the iPhone apps are free, including "lite" versions. Some developers hope to build name recognition or provide a value-added service to customers, such as iPhone apps that complement a Web page. It often helps build a brand.

Provo's FamilyLink.com released FamCam as a free app in April. It's a shortcut way for people to set up groups and send photos quickly by iPhone, says chief technical officer Allan Carroll. The company, which has "We're Related" on Facebook, is now working on a related iPhone app they'll call FamilyLink that enhances the ability to share photos privately with family members and close friends, without risk that the photos of the kids will go places where you have no control. The new iPhone technology means videos can be shared, as well.

Avantar, also in Provo, has six different applications for iPhone, says board member Michael Alvarez. The difference between their movie-finder applications Showtimes and OneTapMovie is where it lets you buy your tickets. Munch searches for restaurants based on what you're craving — sushi, anyone? The only app for which they currently charge is Calculator AXL, a graphing calculator for college students and engineers.