[3] jj met in their hometown of Vallentuna, outside of Stockholm, and began playing together at a local youth center.
For example, they've recorded covers of Akon's "Troublemaker", Jeremih's "Birthday Sex" and the "Theme Song" for the Welcome Back, Kotter TV-series.
[12][13] In late March 2011, jj collaborated with fellow Swedish artist Yves Saint Lorentz to make an official remix of Rebecca & Fiona's single "Bullets".
[15] In summer 2011, jj collaborated with the American R&B singer Ne-Yo and released the song "We Can't Stop" as part of the Adult Swim Singles Program 2011.
[16] Later in 2011, they were involved in another collaboration with American rapper Don Trip to make the song "Cheers (jj's Save Our Souls Remix)" for the magazine The Fader.