Anderson-Lopez and Lopez also composed a simplified pop version (with shorter lyrics and background chorus) which was performed by actress and singer Demi Lovato over the start of the film's closing credits.
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Menzel's version was a single release, being promoted to adult contemporary radio by Walt Disney Records in January 2014. Disney's music division planned to release Lovato's version of the song before Menzel's, as they did not consider Menzel's version a traditional pop song.
Os autores da canção Robert Lopez e sua esposa Kristen Anderson-Lopez explicam as diferenças em esta entrevista com a SSN Insider :
SSN: Pop star and former Disney teen star Demi Lovato sings the song over the end credits. Was she chosen because she is already in the Disney fold? (Lovato is signed to the Disney Music Group’s Hollywood Records)
Anderson-Lopez: Because she is so damn talented. The Disney family thing was very convenient, but honestly, she would have been at the top of the list if she hadn’t been in the Disney family. “Heart Attack” is one of my favorite songs of all time. Not everyone can sing “Let It Go.” It’s not easy. She has the kind of voice that can.
SSN: What’s the difference between the two versions?
Lopez: The bridge. There’s a slight difference between the choruses. It’s slightly rewritten for Demi Lovato. But the real change is the part where Elsa is building the palace in the movie. It’s a totally different section from the equivalent spot on the pop track.
Anderson-Lopez: But both versions tell a story of transformation from fear of letting your power go to letting it come out. Idina will always be our Elsa, and she tells Elsa’s story so well, but it’s very story based. Demi’s is a little more metaphorical where the beat starts driving and driving, but you still get the same feeling of releasing all of this pent-up energy.