Apple made an early iPhone engineer available for an interview with the Wall Street Journal. 

As part of the interview package, it also gave the Journal this photo, which shows how Apple tested the first iPhone.

It used an old Mac to simulate the slow speeds of a phone. It also had a plastic touch screen device, and as you can see, a phone. 

It's a great reminder of how hard it is to make new products. Imagine looking at this and seeing what is the iPhone today. 

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