The 'Lips Are Movin' hitmaker has revealed the pair encouraged her to believe in herself as they fronted a ''new generation'' of popstar.
She said: ''I thought I'd never be famous but then there was a new generation of people - Ed Sheeran, Sam Smith. I felt it was the perfect time for me to say, 'Hey, I'm normal too!' I just want to write music and for people to like it.''
The 21-year-old singer - who is known for her curvaceous figure - used to feel infuriated when she saw ''beautiful girls'' who were just being signed to record labels because of their looks rather than their talent.
She told Top of the Pops magazine: ''There was a period of time when it was just beautiful girl being signed and they weren't even writing their own music or singing that well. In fact, sometimes people came in and sang the hard parts on the songs. I was furious!
''I don't feel like a big girl but I know I'm not a size zero. That was my thing as a songwriter.''