After winning the Critics' Choice BRIT Award in 2010, she released her debut album, Lights, which reached #1 on the UK charts.
She attended the University of Kent, where she discovered electronic music and wrote "Wish I Stayed."
She collaborated with Skrillex on the song "Summit" and her 2010 Elton John cover "Your Song" reached #1 in the U.K.
She has two sisters and a brother. She dated singers Dougie Pointer and Ed Sheeran. In August 2018, she became engaged to Caspar Jopling after just 18 months.
She cited Rihanna one of her influences and sang a cover of her song "Only Girl (In the World)."