She's already the reigning queen of US reality television and has made a stack of cash from a mobile game based on her lavish lifestyle.

And now Kim Kardashian is reported to have set her sights on the lucrative fitness market too with a planned new workout app.

The 34-year-old is claimed by The Sun to be in the "advanced stages" of work on the application, which is intended to help fans get into shape.

A source told the paper: "Kim is hard at work perfecting her latest tech project which will be workout and bum–based.

"She loves working out and keeping fit and is open about it being a struggle. She wants to share her tips as inspiration for others.

"But the app will also be cheeky and fun. An idea is that subscribers will post pictures of their progress, including belfies of their bums getting more toned by the day."

Kimmy had her own workout DVD back in 2009, but the success of her game Kim Kardashian: Hollywood - which apparently made £28m profit - may have convinced her to go cyber for her new venture.