Every time I work with Dr. Luke I learn something new. He's kind of like the Andy Warhol of pop music, where he mass produces his art but it always still has heart and always still has an emotional thread to it. I think he's really a genius and I'm so lucky to have gotten to work with him.

I tend to get a little quirkier and crazier with my lyrics and come from a different angle when I'm writing for myself.

When I go and write with other artists - a lot of the time it's with them - it's like a therapy session almost. I ask them what they're listening to and what they're going through and what their influences are and I try to get inside of their head and step into their shoes for a second.

I've always felt my spirit animal was a Tiger, so it's funny that now in 'Roar' with Katy Perry - which is a song we write together - there's the line: "I got the eye of the Tiger..." So I feel like there's a little bit of me in there.

I've been close friends with Katy since teenagers, before she was Katy Perry. She's always been a great resource for me to pull from and watch - from her choice of how public she wants to be about her personal life on down. I also watched her develop from the coffee-house singer-songwriter I knew to her be to playing arenas and killing it.

Ke$ha is super talented and super fun and always down to party - I love that girl.

I think I've learnt a lot about bullying and how to deal with bullying and how to get over that and to just be yourself and forget the haters.