The eldest of the Keeping Up With The Kardashians sisters showed her support for the brand by wearing a pretty Alice + Olivia olive green jumpsuit and cutting a stylish figure in the FROW.
Kourtney, 36, joined designer Stacey Bendet backstage afterwards.
The reality star has been in New York since the weekend, when she flew in to join sisters Khloe, Kim, Kylie and Kendall at New York Fashion Week.
All five sisters mixed work with pleasure while in the city and visited the Apple Store Soho on Monday to preview their new, official apps. Each star has their very own app which is designed to represent what they are passionate about.
For Kourtney, that is being a mother to kids Mason, five, Penelope, three, and Reign, nine months, and her app will contain features about motherhood, as well as exclusive pictures and videos giving fans an in-depth look at her life
All you need to know about Kourtney Kardashian:
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