What's your guess?

Smartphones really have become an extension of our hands, with the average person spending over four hours a day on their device.

With so much use, they need to be charged daily/nightly, but how much does that cost?

It's something I've often thought about but was too busy scrolling aimlessly through my phone to find out.

Thankfully, Dave's World has the answer.

Dave Moore today revealed that an American company's research has discovered it costs a whopping.........$0.91 annually. Yup, a measly 91 cent (US) - or 82 cent in Euro.

Our trivia champ also tells us why this website haveibeenpwned.com can alert you to hackers and has the science behind the pain paper cuts cause.

Check out his facts in full by pressing the play button on screen.