And Iggy Azalea and Britney Spears teamed up with perform new song 'Pretty Girls' live.
This image appears in the gallery:
All The Photos You Need To See From Inside The 2015 Billboard Music Awards
![Iggy Azalea and Britney Spears Billboard Awards 20](https://assets.capitalxtra.com/2015/20/iggy-azalea-and-britney-spears-billboard-awards-2015--1431937755-view-1.jpg)
22. And Iggy Azalea and Britney Spears teamed up with perform new song 'Pretty Girls' live.
Picture: Getty