Film and Video Festival, Mouser received the Outstanding Performance Award for her voiceover work in Eloise: The Animated Series.

Mouser starred in the ABC medical drama Body of Proof as Dana Delany's daughter, Lacey Fleming.

Mouser also played the roles of both Savannah O’Neal and Emma Reynolds in the Disney Channel Original movie Frenemies, which was released in 2012.

[5][6] Since 2018, Mouser plays high school and karate student Samantha (Sam) LaRusso, in the Cobra Kai series, initially launched by YouTube Premium and later on Netflix, where she is part of the main cast.

In February 2025, when the final season aired, Mouser announced her engagement to Cobra Kai co-star Tanner Buchanan.