SoftBank Mobile
In 1998 or 1999, Japanese mobile operators NTT DoCoMo, au by KDDI, and SoftBank Mobile each defined their own variants of emoji using proprietary specifications. The first popular emoji set was created by NTT DoCoMo employee Shigetaka Kurita for the company's i-Mode service. Compared to SoftBank, au by KDDI included a pile of poo with a different design, without a smiley face.