Hyuna collaborated with Lee Gi-kwang on the song "2009" for his debut album First Episode: A New Hero, and also appeared in the music video of his single "Dancing Shoes," which was released on March 30, 2009.
On August 13, she rapped for Navi's song "Wasteful Tears" and she also appeared in the music video.
Hyuna also featured in Brave Brothers' song "Bittersweet," released August 18.
She became part of the "Dream Team Girl Group," a promotional group for Samsung's Anycall phone with Han Seung-yeon, Uee, and Gain.
Their first digital single "Tomorrow" was released on October 6, 2009, and the official music video was released on October 12, starring actor Lee Dong-gun.
As well, Hyuna released an individual version of the music video which released on October 27.
She also participated in the South Korean variety show Invincible Youth.
However, Hyuna left the show due to some scheduling conflicts with her group's overseas promotions on June 11, 2010.

On January 4, 2010, she released the single "Change", which charted highly on various online charts.
The song reached number fourteen on the Gaon 2010 digital yearly chart with 2,469,354 copies sold.
Ten days later, on January 14, the "Change" music video was flagged with a 19+ rating by the Ministry of Gender Equality and Family for being inappropriate for minors.
Cube Entertainment stated that the music video would be re-edited and submitted for approval.
However, broadcast station SBS, announced the music video would be restricted for a 15+ audience instead, and MBC announced that it would still be viewable for all audiences.
Hyuna's "Change" promotions ended in March 2010.
She released a few more singles in 2010, including "Love Parade" featuring T-max's member Park Yun-hwa, "Outlaw in the Wild" featuring Nassun, and produced by E-Tribe.
Hyuna also participated in G.NA's duet single "Say You Love Me", for which she wrote the rap lyrics.
In October 2010, she made a cameo appearance in the thriller film Midnight FM with 4Minute member Jihyun on October 14, 2010.
Hyuna collaborated with Lee Gi-kwang on the song "2009" for his debut album First Episode: A New Hero, and also appeared in the music video of his single "Dancing Shoes," which was released on March 30, 2009. On August 13, she rapped for Navi's song "Wasteful Tears" and she also appeared in the music video. Hyuna also featured in Brave Brothers' song "Bittersweet," released August 18. She became part of the "Dream Team Girl Group," a promotional group for Samsung's Anycall phone with Han Seung-yeon, Uee, and Gain. Their first digital single "Tomorrow" was released on October 6, 2009, and the official music video was released on October 12, starring actor Lee Dong-gun. As well, Hyuna released an individual version of the music video which released on October 27. She also participated in the South Korean variety show Invincible Youth. However, Hyuna left the show due to some scheduling conflicts with her group's overseas promotions on June 11, 2010.
On January 4, 2010, she released the single "Change", which charted highly on various online charts. The song reached number fourteen on the Gaon 2010 digital yearly chart with 2,469,354 copies sold. Ten days later, on January 14, the "Change" music video was flagged with a 19+ rating by the Ministry of Gender Equality and Family for being inappropriate for minors. Cube Entertainment stated that the music video would be re-edited and submitted for approval. However, broadcast station SBS, announced the music video would be restricted for a 15+ audience instead, and MBC announced that it would still be viewable for all audiences. Hyuna's "Change" promotions ended in March 2010. She released a few more singles in 2010, including "Love Parade" featuring T-max's member Park Yun-hwa, "Outlaw in the Wild" featuring Nassun, and produced by E-Tribe. Hyuna also participated in G.NA's duet single "Say You Love Me", for which she wrote the rap lyrics. In October 2010, she made a cameo appearance in the thriller film Midnight FM with 4Minute member Jihyun on October 14, 2010.
Hyuna