I recently had the opportunity to sit down (virtually) and have a chat with Kyle Richter and Ian Baird, two iPhone developers who have come up with the game-changing Handshake app for contact sharing on the iPhone (TUAW review), then released the credit card and payments app Transactions (TUAW review) which can transform any iPhone or iPod touch into a basic point-of-sale device. We talked about how they came up with the idea of their Transactions application, and they shared their experience of developing for the iPhone.

Cory: What was your vision behind creating Transactions, and why did you pursue this idea and turn it into an iPhone application?

Kyle: When working with a platform that is as new as the iPhone the goal is to try and find niches that haven't yet be filled or not properly filled. While I was out jogging with Ian one evening it hit me that a lot of businesses have a need to accept credit cards anywhere. It felt like a perfect solution for the iPhone so we started to research the feasibility.

Ian: One of the driving influences for us has been to take advantage of the "democratizing force" of the platform. We have Authorize.net for the higher end, more professional users who will use this app on a day to day basis. We also felt we needed to make this application accessible to the farmer who's selling his or her produce at the farmer's market. Or the craftsperson selling his or her wares at a trade show. That was the motivation for including the Paypal option. It doesn't require a merchant account. That's a *big deal*.

Continue reading to hear more from Kyle and Ian about their iPhone programming experience, and advice for prospective iPhone developers.

First they wowed us with Handshake for iPhone, now the same developers are back at it again with Transactions [iTunes link] for iPhone. Transactions gives you the ability to charge a credit card from anywhere! This application is excellent for small business owners who need to process credit cards away from an office.

Transactions interfaces with PayPal and Authorize.net and allows you to easily type in a credit card number, expiration date, CCV2 code, amount, and zip code. Once you have that information, you can select a contact to automatically auto-fill the purchaser's address and phone number. You can also enter in the name, email address, and additional notes about the transaction. When all of these fields are completed, return to the main screen and tap "charge" -- the information is whisked away using 128-bit SSL encryption to the appropriate service (either PayPal or Authorize.net). If the information was correctly entered you receive a message telling you the transaction went through.

Transactions gives you the ability to easily import your PayPal and Authorize.net account information using a useful tool on their site. They send an email to your device with a special URL that inputs your account information when opened. The application allows you to view all of the transactions completed, and allows you to export them as a a CSV file that opens in Excel, Numbers, and other applications that can read comma separated files. All of the information stored within Transactions is kept safe inside of Apple's Keychain, and you can password-protect the application to enable even more security.

Transactions is now available on the iTunes App Store, and comes in two flavors: paid and free. The free version is limited to 2 credit card transactions per 12-hours, while the paid version removes this limit. If you use the free version and plan to upgrade to the paid version, you have the ability to transfer all of your settings from the free version to the paid version -- a first on the iPhone. You can visit the Transactions website for more details about this iPhone application. You may also want to note that Authorize.net or PayPal Website Payments Pro account is required, and that some fees may apply.