Give the scientists early access smartphones, they're not going to get much done while playing candy crush...
Seriously though, just impede the development of lightweight touchscreen technology with a naff up. Smartphones aren't better because they have the technical capacity to perform a lot of tasks, it's that they are easily used for those tasks. My laptop can do video calls, but firing it up and opening Skype is hard, pushing three buttons is easy, especially if they move around depending on if my phone is the right way up. With the right delay, you could have a decade without them.
And before someone says that touchscreen technology has been around for years, I will say 'yes, but it was a steaming pile of equine refuse' I still remember signing for Amazon deliveries and swearing blind that I wasn't El Zorro.