World Emoji Day is celebrated on July 17, the date of the calendar emoji on the iPhone. Since its inception in 2014 by Jeremy Burge, creator of Emojipedia, it rose to dizzying heights of popularity, which may have peaked on July 17, 2017 when Jake T. Austin and Jeremy Burge rang the New York Stock Exchange closing bell.
However emojis have gone to a new level, from static to epilepsy-invoking.
In China, where I live, we communicate almost entirely with WeChat and much of our communication is via sticker. This is a recent conversation about a proposed sushi dinner night.
However not all platforms use July 17 as their calendar icon. Twitter uses July 15 and Android uses a blank month calendar.
365 Holidays a Year 