Scotty McCreery, 17, was crowned as the winner of series 10, with Lauren Alaina in second place.
Here's a round-up of what some stars have been saying on Twitter:
"Me and the boys had so much fun at the #AmericanIdol Finale!! Congratulations @SMcCreeryAI10 may all your dreams come true!!!!! X... Beyonce blew me away at the #Idolfinale!!!! What a performance...and stunningly beautiful, I am loving the blonde hair!!!! x vb"
"Beyonce is operating on different level than everyone right now! #imjustsaying"
"You are not kidding mind blowing performance! RT @aplusk: Beyonce is operating on different level than everyone right now! #imjustsaying"
Judd Apatow, director
"The director of American Idol should lose his DGA card for being so wide during Beyoncé performance. I could see her and half of Los Angeles."
Ashley Greene, actress
"Coachella has nothing on America Idol! Best performers ever! Lady GaGa, Tim McGraw, TLC , Beyonce , Bono , and @reevecarney rocked it! Oh… And carrie underwood, Steven Tyler, Scott McCreery, and Lauren Alaina were Pretty amazing too!!"
Mark Ballas, Dancing with the Stars
"Just watched the idol final in NYC.. @PToscanoAI10 Is my Champion… Love you Pi, so proud of you."
Mena Suvari, actress
"OOOOOOOOOOO!!!!! SUPER SEXY J-LO!!!!!!! The hair, the outfit, the dancing, the body!!!! ShaZAMMM!!! #americanidol,"
Alyssa Milano, actress
"You are amazing @JLo!!!!!"
Cheryl Burke, Dancing with the Stars
"Beyonce is my idol!! She is so inspiring and one of the best entertainers out there today!"
Ali Fedotowsky, Bachelorette
"Tearing up like crazy! Best ending to an #idolfinale that I can remember. So happy for the winner!!! :)"
More on the American Idol season finale:
> American Idol recap: The finale performances
> Beyoncé, Lady GaGa sing on American Idol finale
> Lauren Alaina loses voice before American Idol final
> American Idol finale performance night: Pictures
> American Idol attracts record-breaking votes
> Poll result: Who should win American Idol?
> Read our American Idol news, recaps and features
Watch Scotty McCreery as he performs his winner's song 'I Love You This Big' below: