In 2011, she appeared in Good Luck Charlie, It's Christmas, the film based on the series.Mendler starred in the Disney Channel Original Movie Lemonade Mouth, in which her character Olivia performs numerous songs.Two singles were released from the soundtrack featuring her vocals, with both charting on the US Billboard Hot 100.
In 2004, she began her career in the animated Indian film The Legend of Buddha.
As a teenager, she starred in the films Alice Upside Down, The Clique, and Labor Pains.
In 2009, she signed with Disney Channel and played Juliet van Heusen on Wizards of Waverly Place.
Following the positive reception to her character, she landed the role of Teddy Duncan on the Disney series Good Luck Charlie, which ran from April 2010 to February 2014.
It debuted at number 30 on the US Billboard 200, and has sold over 200,000 copies.
Her debut single off the album, "Ready or Not", became an international Top 40 hit.The song was certified gold in Norway; platinum in New Zealand, the United States, and Canada; and peaked at number 49 on the Billboard Hot 100.It was announced that her second single would be "Hurricane".The video premiered on April 12, 2013 and was shot in London."Hurricane" has been certified gold in the United States.Mendler has links with several philanthropic projects and humanitarian causes.