GRL Max MartinMartin helped write a majority of new G.R.L. music

G.R.L. - 'Vacation' (2013)
Girl bands are making a comeback, and it feels oh so good. With Fifth Harmony and Little Mix running things, the door is certainly open for some new candidates to join them - and G.R.L. seems to be taking advantage of it. Just a few weeks ago the girls dropped their debut EP, and Martin is basically the lifeline of them: he's responsible for their two EP tracks, 'Show Me What You Got' and 'Ugly Heart,' and he even wrote the Pitbull song, 'Wild Wild Love,' which G.R.L. is featured on. However, it's the track that never became a single that happens to be Martin's best G.R.L. work. The group's first ever song, 'Vacation,' was only featured on The Smurfs 2 soundtrack, and it was never heard of again. 'Vacation' was bubbly in the best ways possible, and the first indication that G.R.L. was a very legitimate thing in pop music.

Kesha - 'Wherever You Are' (2012)
Martin wrote Kesha's Warrior track, 'Wherever You Are.' It's an amazing song from a great album. It was never a single. It's still painful to think about. In all honesty, 'Wherever You Are' probably goes down as a top five best Martin track EVER, and it's far and away Kesha's best. It's the complete opposite of a trashy Kesha jam. Instead, 'Wherever You Are' is a simply beautiful, unadulterated pop song, and it would have been a much needed breath of fresh air on Top 40 radio. It's not clear what exactly happened with Warrior and why it only had three singles - only one of which making the top ten - but whatever Kesha is up to now, let's hope it involves a new album soon, with Max Martin right by her side in the studio.

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Simple Plan - 'Generation' (2008)
Perhaps one of the weirdest collaborations in Martin's career is the track he did with pop rock band Simple Plan. It's funny, because despite how unconventional it appeared to be, they proved that it was definitely a winning formula. The track was featured on the band's 2008 self-titled record, and the album as a whole didn't really live up to expectations. The three singles released from the album never made an impact, and it sounded like Simple Plan were confused on whether they wanted to make pop music or rock music. However, their track with Martin fused the two elements greatly, but 'Generation' just never ended up being a single. These days, Simple Plan have mastered the pop + rock art with tracks like 'You Suck At Love' and 'Jet Lag,' so it's definitely time for another Martin studio session to happen soon.