Nir Eyal is the author of Hooked: How to Build Habit-Forming Products and has taught at the Stanford Graduate School of Business and Design School. He has sold two technology companies since 2003 and now help teams design more engaging products. He is also an active angel investor. Some of his past investments include: Eventbrite, Product Hunt, Refresh.io (acquired by LinkedIn), Worklife (acquired by Cisco), Happy Bits, Presence Learning, 7 Cups of Tea, Pana, and Symphony Commerce. Follow him on Twitter: @nireyal.