Add Yahoo as a preferred source to see more of our stories on Google. Scrolling through Instagram recently, I saw a picture that an old friend from high school had posted of his dad with the caption ...

Mobile phone users who send a smiley or sad face, or any type of picture icon, in a text could be stung with massive charges – with one user billed more than £200 as a result of using these emojis.

Pity the poor smiley face. It once was the go-to symbol to convey e-emotion. Cyberspace was its oyster. It reigned supreme. But today's mobile app era has become something of an emoji-eat-emoji world.

It's been a while since the Unicode Emoji Consortium released its sixth set of proposed emojis last June, with a follow up in August (which offered up a drunken face and unhappy poo, oddly enough).