You know the iPad, how could you not. You know the iPhone, you see them everywhere. Over 200,000,000 iOS devices have been sold to date. Its hard not to see at least one of them daily. Most would say Apple's iOS devices are an unqualified success.
Many forget that the iPhone and iPad were not Apple's first foray into the world of personal digital assistants. In the 90's Apple had the "Newton." It was one of the very first PDA's, but it's success was far less certain. While some still exist today, the Newton was shelved by Steve Jobs in 1997 shortly after his return.
Amazingly the Newton did much of what the iPhone or iPad do today, but in ways that will seem ancient to anyone under 25. Check out the modem. The Newton could fax too, the iPhone can't fax.
This commercial will give you a very good idea of the Newton. I actually held one years ago. It was truly ahead of it's time. Just too big and too expensive for what it could do.