From the original iPad's launch event (January 27th, 2010,) these are the six tasks Jobs listed at which the iPad was to exceed the laptop and the smartphone.

iPadTasks.md

In order to really create a new category of devices, those devices are going to have to be far better at doing some key tasks. They're going to have to be far better at doing some really important things better than the laptop [and] better than the smartphone.

1. Doing email.
2. Enjoying and sharing photographs.
3. Watching videos.
4. Enjoying your music collection.
5. Playing games.
6. Reading ebooks.

If there's going to be a third category of device, it's going to have to be better at these kinds of tasks than a laptop or a smartphone. Otherwise, it has no reason for being.