A DJ situated at the top of the store's grand staircase spun selections from each singer's upcoming album while guests nibbled on hors d'ouevres and sipped mojitos.
JoJo told ShowBuzz that it was fun to throw the party at one of her favorite stores. "I love Sephora. I would have come by to do some shopping during the day anyway!"
Her sophomore album, "The High Road," is scheduled for release Oct. 17, and the set's first single "Too Little, Too Late" is already out and doing well.
"It's the No. 1 video on iTunes," she said proudly, "No. 1 requested (song) on top 40, so it's very exciting."
Teen trio The Jonas Brothers, who released their debut album, "It's About Time," earlier this month, were among the guests along with gossip blogger Perez Hilton.
Mya looked gorgeous in a slinky dress and spike-heeled boots, but she told ShowBuzz that she's not a girly-girl — most of the time.
"When I go to the spa, I'm a girly girl," she said. "I'm pampering myself. But, on a regular basis I'm a very tough tomboy — I have to remind myself that I'm still a woman! My nails get a little dirty; I box a lot and shoot guns."
The Grammy-winning singer added that perhaps she's a tomboy because she has "nothing but brothers and no bigger sisters to … keep me in check."
Mya said her upcoming album, "Liberation," out Nov. 14, is her most vulnerable and personal album yet.
"I think people are going to get to witness some of my past insecurities with my family, divorce, my views on cheating," she said. " 'Liberation' means to be set free. ... I've been through a lot of transitions that have made me better so I have a more positive outlook on everything. My problems are so miniscule compared to what's going on in the world, in that sense I feel liberated."
Like many artists, Mya said the process of making the album, came very close to therapy.
"I've been honest with myself and have been able to admit some things and analyze myself and save myself at the end of the day," she said. "But it's still entertaining; you don't get too depressed when you're listening to my album!"
She added that her new single, "Ayo," is about how she "parties and gets down." She admitted, though, that it does address a rocky relationship with her ex-boyfriend, but "it was closure. We're friends now."
By Judy Faber