In 2012, Mendler released her debut album, Hello My Name Is..., which debuted at number 30 on the Billboard 200 chart. The album's lead single, "Ready or Not", peaked at number 49 on the Billboard Hot 100 chart. Mendler has also toured with Selena Gomez and Demi Lovato.
In 2014, Mendler starred in the Disney Channel Original Movie Girl vs. Monster. She also released her second album, Nemesis, which debuted at number 89 on the Billboard 200 chart. The album's lead single, "Hurricane", peaked at number 94 on the Billboard Hot 100 chart.
Since then, Mendler has continued to act in various television shows and movies, including Undateable (2015-2016), Merry Happy Whatever (2019-2020), and The Secret Life of Pets 2 (2019). She has also released several singles, including "Atlantis" (2016), "Do You Miss Me at All" (2017), and "Diving In" (2019).
In addition to her acting and singing career, Mendler is also an active philanthropist. She is a UNICEF Goodwill Ambassador and has worked with various charities, including the Make-A-Wish Foundation and the Starlight Children's Foundation.