In 1999, he applied to go on the ITV talent show, Stars in Their Eyes, where he appeared as Simon Fowler of Ocean Colour Scene.
In 2001, Simm auditioned for the ITV reality television music competition Popstars, a show intended to form a new group from individual contestants, becoming one of the finalists.
While the five winning contestants formed Hear'Say, the five runner-up contestants – Simm, Tony Lundon, Jessica Taylor, Kelli Young and Michelle Heaton – formed the group Liberty X and signed a multimillion-pound record contract with Richard Branson and V2 Records.
[8] In 2013 Simm reunited with Liberty X for ITV2's reality show The Big Reunion, along with other pop groups of their time – B*Witched, Honeyz, 911, Five and Atomic Kitten – to solve past problems and do a live performance at the London Hammersmith Apollo on 26 February.
[11] In 2017, Heaton, Jessica Taylor and Kelli Young reformed Liberty X again, but as a three-piece girl group, without Kevin and Tony.
[14] In the same month, Simm signed with Universal and released his new single as The Voice winner, "All You Good Friends"; the song peaked at number 24 in the UK and 3 in Scotland.