Soon you may no longer require a normal landline to connect your Credit Card processor. Developed by Square, a company inspired by Twitter Inc. creator, Jack Dorsey allows everyone to accept credit card payment using a tiny device attached to the headphone jack on iPhone and processed by a software that is downloadable to the smartphone.

Besides iPhone, the credit card reader also supports Android-based smartphone and works with the phone’s software prior processing the software via Square’s secure payment gateway servers. The applications for other mobile phones such as Blackberry and Palm Pre are also in development.

Once the card swiped onto the reader, the buyer will have to sign for the transaction using their finger strokes on the smartphone’s touch screen. Unlike a normal credit card processing, a receipt will not be printed, instead you will be issued with a digital receipt sent to your email address which you need to type on the screen.

The person processing the credit card will be charged by Square a fee of 15 cents per transaction in addition to 2.75% of the total value charged to the card holder. In other words, an total amount of $4.25 will be charged for a $100 sales transaction. Users also can manually key in their credit card number but the charges will be higher.

In term of security, Square has taken additional steps to protect personal information using a sophisticated encryption program to ensure data integrity and to build up trust to the customers.