The original iPhone (2007)

Apple's first iPhone from 2007 was the one that started it all. It had a 3.5-inch screen, a 2-megapixel camera, and topped out at just 16GB of storage. It didn't even support third-party apps yet.

While those specifications seem primitive compared to today's super-powerful smartphones, the original iPhone was critical in setting the standard for mobile devices in generations to come. Its multi-touch display, for example, was crucial in paving the way for the touch-based operating systems found on smartphones, tablets, and computers around the world.