KTF
KTF (Korea Telecom Freetel, Korean: 주식회사 케이티프리텔) was a South Korean telecommunications firm, now merged into Korea Telecom, specializing in cellular, or mobile, phones. Since 1999, it has also developed extensive overseas operations. The company is credited with developing customised ring back tones. On 1 June in 2009, KTF was merged with KT.
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