The evidence correlating the decline of mental health for kids and teens with the rising use of smartphones is undeniable.  It's all laid out there for us to see.  There's a lot of food-for-thought in this book, and it was at times very disheartening.  Essentially a whole generation of kids have been experimented on, with heartbreaking results.  While overall this book was very engaging and informative, I did find that some ideas became very repetitive - but maybe that's on purpose - perhaps that's what parents need to become proactive.  The 'In Sum' sections at the end of every chapter will make revisiting the ideas in this book in the future very helpful.