It's always on, always listening, always notifying you when you should do things. Algorithmically telling you what to hate, in two minute videos. Not having one is akin to exile from society. What was really a stroke of brilliance was making them portable and convincing us to pay for them, rather than making them mandatory and provided by the State.
Absolute genius, I could not have done it better! My telescreens are Xiaomi/Huawei -- I would feel lonely if only the West was listening. They are quite wonderful little things.