We all know that Apple's iPhone is the best-selling smartphone in the world. But does anyone know that this gadget can be used in film-making?

South Korean film director Park Chan-wook has done just that.

Chan-wook, who is known for his works such as Old Boy, ''Lady Vengeance, said his new film Paranmanjang was shot entirely on the Apple Inc.'s iconic smartphone.

Paranmanjang, which means a life full of ups and downs, is a short fantasy-horror movie and is about a man going beyond his current and former lives.

The movie, made on a budget of 150 million won ($133,000), was shot using the iPhone 4 and is set to hit South Korean theaters on Jan. 27.

The new technology creates strange effects because it is new and because it is a medium the audience is used to, Chan-wook told reporters.

Park's younger brother Chan-kyong said that a wide variety of angles and edits were possible because numerous cameras could be used.

There are some good points of making a movie with the iPhone as there are many people around the world who like to play and have fun with them, Park Chan-wook said. Compared to other movie cameras, the iPhone was good because it is light and small and because anyone can use it, he said.

He said the directors attached lenses to their phones and nothing was particularly different from shooting a regular movie.

Cupertino-California-based Apple introduced its first iPhone on January 9, 2007. An iPhone functions as a camera phone, including text messaging and visual voicemail, a portable media player, and an Internet client, with e-mail, web browsing, and Wi-Fi connectivity. The user interface is built around the device's multi-touch screen, including a virtual keyboard rather than a physical one.

The latest generation of iPhone -- iPhone 4 -- was released on June 24, 2010 and has two cameras for FaceTime video calling and a higher-resolution display.

For the recently concluded quarter, Apple said iPhone sales jumped 91 percent to 14.1 million and speculations are rife that iPhone could come to Verizon's network next year. Currently, AT&T is the exclusive carrier of iPhone in the U.S.