Hooked: How to Build Habit-Forming Products by Nir Eyal
My rating: 4 of 5 stars
Meticulous, well research and concise. This book has received a lot of attention in and for good reasons. If I was building a business right not and had to solve the problem of engagement and was allowed only one book to reference from, this would be it and I think that in itself says a lot. It is not perfect, but Nir gets his ideas and research across very clearly which is something valuable.