01/25/2013 at 06:50 PM EST
gambled the night away at The London West Hollywood hotel on Thursday evening – but it was all in good fun.
The pop star, 28, wearing a form fitting black Cavalli dress with sparkly purple accents – joked with fellow guests and table dealers on the rooftop as she played her way through several games of Blackjack and craps.
"I created the Popchips bag and I wanted [my dress] to fit with the bag," she told PEOPLE as she celebrated the launch of her new flavor: Katy's Kettle Corn. "That's kind of what I do! I always want to add more sparkles to everything I do."
– Melody Chiu