The iPhone turns 4.

Yo Yo Yo..!!!

Four years ago, Apple's first iPhone went on sale, a benchmark that comes at a time when all eyes are on the company to announce a fifth-generation of the device.

It's easy to look back at the iPhone's rise and success and see how it's managed to work out so well: Apple took aim at a product category with the same approach it used with the iPod, creating its own hardware and software, then eventually bundling it with extra services and features. Proof enough of that is the App Store, something that began with Apple's mobile devices, and has since jumped across to the company's computers with the Mac App Store.

But when the original iPhone was announced, many wrote it off before it even hit store shelves. There were issues like the price, the hardware, the feature set, and what carrier Apple was going with. But more than anything it was just the doubt that the company could venture into new territory with all these variables and find success.

The iPhone has gone on to become a company-defining product, transforming Apple's image of a computer maker with a hit portable music player and booming music service into a major player in an industry it merely dabbled in as an unsuccessful partner with Motorola just years before. In Apple's most recent fiscal quarter, the iPhone made up around half of the company's monster revenue. It's also had an impact on other Apple products, spilling out design ideologies to Apple's Mac OS X operating system, and the company's notebook computers.

Below are a smattering of predictions from pundits (including us), along with Apple competitors, all placing bets on where the product would land with consumers and the market ahead of its announcement and eventual release.