There were many instances where administrative services were much more accessible through an app or QR code than anything else. Also, in the enrollment center, when you entered the queue you would divulge your SMS number, and there was a screen which displayed who was waiting, and you'd receive SMS notices when your number came up.
Other instances included special apps for the Student Life folks, and QR codes on practically every official poster around campus.
As I say, I was able to get by without a phone and only a WiFi tablet, but sometimes I felt like a second-class citizen without a phone. I did use a notebook for classwork, but I rarely ever took the notebook on campus, just to experiment with the settings. I typically made use of the lab computers instead.
As for notebooks, yes, they are more useful for schoolwork and research, but again, the student terminals were ubiquitous in labs, libraries, and coffeehouses alike, and in the classroom for e.g. Group Communication, who needs a notebook for that? We were actually encouraged to write journals in a paper notebook, we'd turn them in and be graded by the instructor. He didn't really make a provision for electronic submissions at that point. So students would only bring their phones.
Theft is rampant and endemic on every college campus. You do not want to bring big-ticket items if you can avoid it. Therefore, any student who did not absolutely need a full-blown computer would not even put it in backpack. Students brought only phones to class; easy to pocket and easy to keep track of. It was easy enough to have a full-fledged computer at home that you would use for schoolwork and research, and most of us found it unnecessary to bring such a thing to a classroom. If we needed a computer during class, then they were already sitting on the desk in the classroom, and we'd need to sort of shove it out of the way to put our notebook down, and the WiFi was inferior to the wired GbEthernet connection on the lab computer, which had all necessary software installed, so why bother at that point?
There was a kid in our PC/Windows class who brought in a fantastic gamer PC notebook. It was ostentatious, had lots of shiny LED effets, and was big and heavy, especially its custom power brick. I sort of chuckled at that expense he made because it did not make a lot of student sense. It was not a few weeks before he was embroiled in an RMA because the power brick had indeed malfunctioned, and he'd had his heart set on using the personal machine instead of the lab machines.