Cal Newport's _Digital Minimalism_ goes into this quite a bit. It's worth the 250 easy pages, I think.

In the first half of the book he makes the case that smartphone addiction in particular is much more harmful to society than immediately obvious. Many people nowadays spend literally zero time just alone with their thoughts, ever. Unlike with the previous decade's simpler "Internet addiction," even those brief moments when we used to be forced to do so, whether we liked it or not -- like waiting on line at the store -- are gone. He argues that this has extreme deleterious effects on our mental health. The situation is especially dire with the generation that has grown up knowing no other way.

The second half of the book consists of various techniques ("practices") to combat this in our own lives. (More useful ones, than e.g. "delete facebook")

Maybe I am taking this too seriously, but I find this kind of parallel unhelpful at best. Smartphones themselves are a huge time sink for a lot of people that is absolutely true and I have no doubt that it can also be considered an addiction.

That being said, smoking is a health problem that has no positive impact at all on our society. By comparison, smartphones can be used as a tool to access a treasure trove of information online. From obscure claims your brother-in-law can make to looking up recipes when cooking, without forgetting learning a language on the bus with Duolingo. Therefore, I think smartphones are above all a very useful tool, and I believe perhaps foolishly that in time we will find an equilibrium that does not include going back to not having one.