Rote learners don't need a phone book in their phones. They will learn all the phone numbers eventually when they have nothing left to learn.

When I was a child I knew the phone numbers of all my classmates and my family and I still remember a fee of them even though I've not used them in over thirty years.

Smart phones, while useful, are ruining people and making us mentally lazy.

Just one without efforts.

I can remember hundreds of phones numbers.