Kan Pebrero 2015, nakipagtabangan si Grimmie ki Dove Cameron asin nag-gibo nun music video para sa "What A Girl Is", an orehinal na kanta hale sa show ni Cameron na  Liv and Maddie. Ipinaluwas an music sa channel ni Grimmie asin sa YouTube channel man kan Disney. Kan Marso 4, 2015, inanunsyo ni Grimmie na nagbutas na siya sa Island Records huli ta ginigibo niya an bagong album set na ipapaluwas sa katapusan kan 2015 . An bagong single sa album na "Cliché" ipinaluwas kan Marso 16, 2015. Kan Abril 27, nagluwas si Grimmie kan ika-duwa niyang single na "Stay with Me" sa pakikipagtabangan sa Diamond Eyes na nagin ika-lima sa iTunes Electronic Charts. Napasali an kanta sa 2015 UKF Dubstep, sarong album na naglalaman nin top dubstep songs of the year. She was also a contestant in the iHeartRadio/Macy's Rising Star Contest. On May 27, 2015, Grimmie was revealed as the winner of the contest, securing her spot to open the 2015 iHeartRadio Music Festival in September. On July 2, 2015, she released her third single, "Shrug". In September 2015, she was one of 16 international artists including Paul McCartney to record the charity single "Love Song to the Earth", which raises climate change awareness. Grimmie returned to The Voice for season 9, to promote Kohl's fashion.