Robertson first appeared before an audience when performing various roles on stage at the Greenville Little Theater in her hometown. At age 12, she began making extended trips to Los Angeles to audition for roles in television; she was cast in a role in a
pilot for a series which was never picked up by a network. She made her screen debut as the younger version of the
title character in an episode of
Sheena in 2000. She made a guest appearance on
Power Rangers Time Force the following year and received a
Young Artist Award nomination for
Best Performance in a TV Movie, Miniseries, or Special – Leading Young Actress for her role in
The Ghost Club (2003). Robertson was selected to play Michelle Seaver in the
Growing Pains: Return of the Seavers in 2004. A role in
Keeping Up with the Steins followed in 2006. She played Cara Burns in the 2007 film
Dan in Real Life. Robertson appeared in
CSI: Crime Scene Investigation in the episode "
Go to Hell", and had a role as a recurring character in the
CBS television series
Swingtown. In 2008, she played the protagonist in a
Lifetime original film,
The Tenth Circle, based on
Jodi Picoult's
novel of the same name, followed by other television roles. In 2009, she appeared in
Mother and Child. In the same year, she played a small role as DJ in
The Alyson Stoner Project. She also made a guest appearance on
Law & Order: Special Victims Unit in the episode "Babes" as Tina Bernardi, a Catholic teen who gets pregnant in a pact. In late autumn 2010, she starred as Allie Pennington in the
Disney Channel original film
Avalon High. Robertson played the lead role of
Lux Cassidy in the television drama series
Life Unexpected (2010–2011), which was cancelled in its second season despite positive reviews. In 2011, she appeared in
Scream 4. She also had a leading role in the
supernatural teen drama television series
The Secret Circle (2011–2012), but after its first season, it was also cancelled. That same year, she starred in the film
The First Time. ,
Pihla Viitala,
Zrinka Cvitešić,
Freida Pinto and
Jessica Chastain at the 2010
Hamptons International Film Festival In 2013, she joined the main cast of the science fiction
mystery television series
Under the Dome in the role of Angie, which she played until 2014. She had subsequent roles in the films
Delivery Man (2013) and
Ask Me Anything (2014), for which she won the
Best Actress award at the
Nashville Film Festival. In 2014, Robertson won the
Boston Film Festival Award for Best Supporting Actress for
White Rabbit. In 2015, she starred in
The Longest Ride, and also played the starring role in the film
Tomorrowland, for which she was nominated for the
Teen Choice Award for Choice Movie Actress – Sci-Fi/Fantasy. Robertson received wider recognition in 2015 after landing the roles of Sophia Danko in
The Longest Ride; she received a nomination for the
Teen Choice Award for Choice Movie Actress – Drama. In 2016, she starred in the films
Mr. Church and ''
Mother's Day, and in 2017, she starred in the science fiction romance film The Space Between Us and in the comedy-drama film A Dog's Purpose. That same year, she headlined the Netflix comedy television series Girlboss, portraying a fictionalized version of self-made millionaire Sophia Amoruso. She starred in the ABC legal drama For the People'' for its entire two-season run. In April 2019, Robertson was cast in the role of Melissa Henning, the real-life wife of
Christian rock musician
Jeremy Camp, in
Lionsgate's
faith-based biographical romance film I Still Believe. The film was released in March 2020. In January 2021, Robertson was added to the cast of the ABC drama
Big Sky as recurring character Cheyenne Kleinsasser. On July 30, 2021, Robertson was cast in the upcoming independent film
The Re-Education of Molly Singer as the title character. ==Personal life==