The presenter - whose parents are Black Sabbath rocker Ozzy and -America`s Got Talent` judge Sharon Osbourne - was astonished when she got her recent statement as she thought she had been careful to curb her cell phone use while in America competing in reality TV show `Dancing With The Stars`.
She said: "Oh, my God, I`ve just had my most expensive phonebill. Do not have an iPhone if you travel because it seems like they charge you every single time you even press a button on your applications. My bill was £2,500. And I was making a conscious effort not to use it so much."
However, Kelly - who is engaged to model Luke Worrall - didn`t run up the bill speaking to Ozzy, though she admits her close bond with Sharon was a contributing factor.
She added to Britain`s Cosmopolitan magazine: "My dad is really bad with his phone. The conversation only lasts about three seconds but it`s just nice to speak to him.
"I speak to my mum about 20 times a day. I find any excuse to call her as I just like talking to her."