"Go Go Summer!" (GO GO サマー!, Gō Gō Samā!^?) is the fourth Japanese single of South Korean girl group Kara. The song was released digitally on iTunes Japan on June 22, 2011, while the full single was physically released on June 29, 2011. It is the group's second Japanese single to sell over 100,000 copies during its first week, following their third single, “Jet Coaster Love“, which sold 123,000 copies during its first week. It was certified gold by the RIAJ in June 2011 for physical copies shipped to stores. It was also the group's first single to be nominated for the "Best Song Award" at the Japan Record Awards.

It was released in four different versions, three limited editions and one regular edition.

A 2012 version of the song was released for 's karaoke system "Furikara". This version remains its original lyrics but with a different electronic instrumental. It was released digitally in July 25, 2012.

Rumors of a fourth Japanese single first surfaced when the group was spotted leaving the Incheon International Airport and were said to be bound for Thailand to film a music video or a commercial. Despite the rumors, no official announcements or comments were made by DSP Media. On May 25, 2011, DSP Media officially announced that Kara will be releasing their fourth Japanese single in late June and will be leaving for previously-arranged promotions in early June.

On June 1, 2011, it was announced that the girls will be the newest models for the upcoming cellphone brand from LG called "Optimus Bright" (known as Optimus Black in certain markets) and that they will also be releasing a new Japanese single titled "Go Go Summer!", which will be used in the commercial for the brand while being promoted at the same time. The B-side "Girls Be Ambitious" was used for promoting DARIYA’s hair dye product line "Palty".

...
Wikipedia