SEOUL, Nov. 11 (Yonhap) -- Apple Inc.'s iPhone 4S was released in South Korea on Friday with great fanfare as the country's two largest mobile carriers heated up their competition to lure customers.

SK Telecom Co., South Korea's largest mobile operator, and the runner-up KT Corp. invited fans to celebrate the arrival of the iPhone 4S, the first Apple smartphone that the two archrivals have launched concurrently.

At midnight, SK Telecom invited the first 100 people who placed pre-orders for the iPhone 4S to activate the handset before dawn and join celebrations with popular Korean hip-hop artists.

"I feel great to be the first iPhone 4S subscriber in South Korea," said Lee Jae-kwang, a 31-year-old man who lives in a suburb of Seoul.

At KT's flagship store in central Seoul, Apple fans reenacted the ritual commonly practiced by global Apple fans on the first day of a product lunch, forming a long queue before sunrise.

"I'm most looking forward to the iCloud and photo-streaming ability of the iPhone 4S," said college student Kim Myung-gi, who arrived at 6 a.m. to start queuing. ICloud is the name of Apple's new remote, online storage system that wirelessly saves files and photos from the smartphones. 

KT was the first mobile carrier to release Apple's iPhone in the country in 2009.

Apple's iPhone 4S, one of the last products created during the lifetime of Steve Jobs, Apple's leader who died last month after a battle with cancer, sports a voice assistant function called "Siri" and a string of new features from the updated operating system.

The iPhone 4S is expected to stack up against the Galaxy series of smartphones from Samsung Electronics Co., including the upcoming Galaxy Nexus, to attract the country's rapidly growing smartphone users.

The number of South Korea's smartphone users reached 20 million at the end of October, less than two years after the iPhone's debut in the country. The country has around 50 million mobile phone users.