The number of smartphone users in South Korea is set to surpass the 20 million mark in November as local handset makers roll out new smartphone models, data showed Sunday. As of the end of September, the total number of smartphone users in South Korea reached 18.8 million, according to data compiled by three major mobile operators including SK Telecom. Market watchers said given that the number of users is growing by around 40,000 to 50,000 per day, the number of smartphone users is expected to breach the 20 million mark no later than next month. In March, the number of smartphone users passed the 10 million milestone. The popularity of smartphones has been heating up since Apple Inc.\'s iconic iPhone was introduced in the Korean market in November 2009, bringing a seismic change to the local smartphone markets. The number of mobile phone users in Korea reached 52 million as of the end of August, indicating that four out of 10 Koreans are using smartphones. The smartphone market in South Korea is likely to become increasingly bullish as smartphones using fourth-generation (4G) network will be on the market, market watchers say. SK Telecom Co., South Korea\'s largest mobile operator, plans to offer seven smartphones and one tablet PC that use its new 4G service based on the long-term evolution (LTE) technology this year in a bid to meet surging demand for video and other data-guzzling services.