Demi Lovato is set to let her fans decide where she visits on her European tour in a ground-breaking promotion.

The pop star, 21, will determine which cities she includes on her Neon Lights tour by the number of Shazam tags that are generated for her current single - also called Neon Lights.

The places that prove most popular with Demi's fans on the music app will then be worked into a tour itinerary.

Demi said: "I am thrilled to collaborate with Shazam on such a unique promotion which puts my future in my Lovatics' hands by allowing them to pick which cities I visit!

"I can't wait to bring the 'Neon Lights' tour to Europe!"

The promotion starts today and runs for the next three weeks. The results will be announced next month when Demi is in the UK.

Demi recently went make-up free for a selfie.