U.S. tech giant Apple Inc. officially began sales of its first smartwatch in South Korea on Friday, heralding a fierce battle with Samsung Electronics Co. to gain the upper hand in the wearable market.

Along with six other countries, the Apple Watch is now available at online and offline shops in South Korea, roughly two months after it went on sale in major markets including the United States and China.

While the Apple Watch boasts similar key technologies as other wearables such as healthcare-related features, the device is unique in that it allows what it calls a "new kind of conversation," including sending a finger sketch to other users.

It does not, however, come with a separate universal subscriber identity module (USIM) card that allows it to make calls independently like Samsung's Gear S or LG Electronics Inc.'s LG Watch Urbane LTE, but must be linked to smartphones through Bluetooth within a 10-meter distance.

Unlike the United States, the U.S. firm's Apple Pay system is not yet available in South Korea.

The Apple Watch has been gathering strong popularity abroad, with industry tracker Slice Intelligence claiming its sales have reached 2.79 million units through June. It hovers far above the around 2-million sales boasted by Samsung's six wearable devices launched since 2013.

Samsung earlier said that it plans to release its first round-type smartwatch, but it is yet to provide a detailed launch schedule, thus giving Apple the upper ground in the local market for the wearable segment. (Yonhap)