Guests in attendance included Jonah Hill, Erin Heatherton, Robert Downey Jr., Candice Swanepoel, Jason Segel, and Levine's bandmates James Valentine and Jesse Carmichael.
Levine and the Victoria's Secret model started dating in June 2012, and following a brief split, they got back together and announced their engagement last July.
Kourtney and Kim Kardashian both wore bra tops when they went to dinner at Ostra in Costa Rica on Friday evening. The 32-year-old Revenge Body star covered up a bit - well, covered up by Kardashian standards - with a maroon top and jeans, no doubt from her Good American line.
Her maroon top was skin tight and off the shoulder.
In 2007, she received the Brit Awards "Critics' Choice" award and won the BBC Sound of 2008 poll.
Her debut album, 19, was released in 2008 to commercial and critical success.
At the 51st Grammy Awards in 2009, Adele received the awards for Best New Artist and Best Female Pop Vocal Performance.
The super star has been working out one hour a day and is on the Atkin's Diet.
This comes after the wife of Kanye West modeled nothing but a low cut black tank top during a Snapchat session with kids North West and Saint.
Khloe's jeans, which had an uneven split hem, were snug as can be, And the Cosmo cover girl still had on her tight braids from her recent trip to see beau Tristan Thompson of the LA Lakers.
The beauty kept her head down and did not appear to be in the best of spirits/Sister Kourtney has been linked with both ex Scott Disick (they are reportedly back on) and Justin Bieber in recent weeks.