Iggy Azalea collaborated with some pretty epic artists as of late, but two of our faves are undoubtedly Britney Spears and Ariana Grande. Which duet do you like better?

Iggy Azalea and Britney Spears just dropped "Pretty Girls," and needless to say the editors at PopCrush totally lost our minds. "Pretty Girls" is already our Summer 2015 anthem, mostly because of its infectious, electric beat and the fact that Britney is totally channeling Gwen Stefani throughout the whole tune (seriously, she sounds like she could be Gwen)! Both Britney and Iggy bring the girl power throughout the upbeat track, and we can't help but sing it at the top of our lungs, especially lyrics like, "All around the world pretty girls wipe the floor with all the boys." Tell 'em, ladies.

"Problem" will always hold a special place in our hearts, since it was this insanely catchy track that catapulted both Ari and Iggy into serious superstardom. Seriously: No matter how many times we hear those opening horns or Iggy yell "I got one more problem witchu girl!" the song will never get old. Whether it's Ariana's breathy vocals on the chorus or the fact that we can rap Iggy Azalea's entire bridge like total bosses (whattup), "Problem" will forever be our go-to jam.

Which Iggy collab is your fave? Vote Britney Spears or Ariana Grande in the poll below!

Listen to Britney Spears + Iggy Azalea's "Pretty Girls"

Listen to Ariana Grande + Iggy Azalea's "Problem"

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