Obviously, the iPhone definitely is worth mentioning in this section. When the iPhone was introduced in 2007, I recall it being the most hotly anticipated product. My friends were all cooked around those select few people in my school who owned one. Also keep in mind that the original iPhone was $500 dollars WITH contract. So altogether, this phone was a rare sight, but it didn't stop it from being one phone remembered for revolutionizing the cellular phone world. The iPhone 3G, however, I was slightly disappointed at how little improved the phone was. Infact, overall stability of the phone decreased, and the same old hardware was used to support a 3G network connection, which proved to be a mistake. The iPhone 3G was a very sluggish, unstable phone when compared to the likes of other phones. However, apple made up for itself with the release of the 3GS, which addressed these hardware concerns. The 3GS was faster, more stable, and sported some additional minor hardware improvements, like the camera and compass. I loved the 3GS, which is why I own one today. The iPhone 4 isn't a bad phone, but I was disappointed to know that it had a minor flaw with the antenna design. Although it is fixable, it isn't a good thing to know your phone has a small flaw with it in the first place. But overall, iPhone is a successful product, and I am really amazed at Apple's innovation with their design. It truly is a revolutionary product.