It was written by Mia and Tyga alongside George Veikoso, Marc Griffin, and producer Nic Nac (J Boog received a writing credit for the sampling of "Let's Do It Again").

The song attained platinum or multi-platinum certifications in five countries and appeared on the 2015 year-end charts in Australia and the United Kingdom at positions 53 and 60 respectively.

Mia performed "Do It Again" at an American Express concert and as an opening act on Jason Derulo's Australian tour leg in 2015.

In April 2020, a dance challenge of the song uploaded by Noah Schnapp on social media platform TikTok went viral, with celebrities such as Jimmy Fallon, Jennifer Lopez, Charli D'Amelio, and Addison Rae participating.

[3] In 2014, after the song finished production, Mia walked into a studio session with Nic Nac, Chris Brown and Tyga, when "Do It Again" was played.

[7] In September 2014, British radio presenter Max announced on Twitter that Mia had enlisted Brown and Tyga to appear on "Do It Again".

[8] The song was released on digital download and streaming formats on May 4, 2015, and was distributed to rhythmic radio stations in the United States on May 11, 2015.

[1] "Do It Again" opens with synthesizers that utilize a crescendo,[19] as Tyga raps in the first verse before Mia appears to sing 30 seconds into the song.

[6][14][16] Writing for Teen Vogue, Tehrene Firman stated that the song is "fun [and] catchy",[6] while Mike Wass of Idolator opined that the anthem is "infectious".

[14] Writing for the Belfast Telegraph, Blast 106 disc jockey Kathryn B Wilson described "Do It Again" as "infectious" and praised Tyga's rap verse for "[setting] a decent tone for Mia's vocals".

[27] The song was ranked at number 60 on the 2015 year-end chart,[28] and certified double platinum by the British Phonographic Industry (BPI) for sales and streams of 1,200,000 units on June 24, 2022.

[39] Mia wore two Guam seal pendants,[40] while Brown's attire consisted of matching yellow Dsquared² embroidered jacket and hockney pants, with white Nike Roshe Run shoes.

[36] The video begins with Tyga rapping atop a cliff facing the ocean,[2] which transitions to Mia sporting a red bandana in a white Jeep Wrangler with two other women while being driven along the coastline.

[2][35] Mia rolls around in the sand and frolics on the beach,[45] before rendezvousing at a late night party in a cabana with Tyga and Brown.

[2][43][45] Mia performed "Do It Again" at the American Express Unstaged: Artists in Residence summit on August 20, 2015, which also included Rae Sremmurd, Børns, and Gavin James.