Ahead of the hotly-anticipated announcement, click through to see how Apple's signature product has evolved through the years.
quicklist: 1title: Introducing the iPhonetext: Steve Jobs wasn't kidding when he called the iPhone a "revolutionary and magical product that is literally five years ahead of any other mobile phone."
While other phones on the market used buttons, the first iPhone model introduced the experience of using fingers to scroll.
It was also the beginning of the shift in how we exchange messages with friends, family and colleagues. The first iPhone came with Apple's visual voicemail, meaning no more cluttered voicemail boxes. The feature, which is a staple on iPhone's to this day, gives users a listing of their messages and lets them decide which one they'd like to listen to first.
quicklist: 2title: iPhone 3Gtext: The announcement of the iPhone 3G ushered in the age of the app.
Building on the success of the first iPhone, the 3G, which went on sale in 2008, included iPhone 2.0 software equipped to run hundreds of third party apps through Apple's new App store. (The number of apps available in Apple's app store surpassed the 1 million mark in 2013.)
The smartphone also included built-in GPS for expanded location-based mobile services -- a must have feature on every smartphone available today.
quicklist: 3title: iPhone 3GS text: Apple continued to build on its success by releasing the iPhone 3GS -- a smartphone they said was even faster and more powerful than previous models.
Released in 2009, the phone was on average twice as fast as the 3G -- allowing more users to turn to their phones to surf the internet.
It also boasted new features including an autofocus camera, video recording and the freedom of voice control.
quicklist: 4title: iPhone 4text: A sleeker, thinner iPhone made its debut in June 2010.
The iPhone 4 introduced FaceTime to the world -- allowing users to make video calls from anywhere in the world as long as they were hooked up to a WiFi connection.
With a retina display and a five megapixel camera, many users were inspired to ditch their point and shoot cameras in favor of using the iPhone's photo features.
quicklist: 5title: iPhone 4Stext: In October 2011, the world met a lady named Siri.
Apple's intelligent virtual assistant was introduced as one of the key features of the iPhone 4S in October 2011.
The 4S also boasted an "all new camera" -- perfect for burgeoning iPhone photographers, and full 1080p HD video recording.
quicklist: 6title: iPhone 5text: If there was a smartphone beauty contest, the iPhone 5 would have won hands down when it burst onto the scene in September 2012.
The 5 was thinner, lighter and faster than its predecessor.
"[The] iPhone 5 is the most beautiful consumer device that we've ever created," said Philip Schiller, Apple’s senior vice president of worldwide marketing, said at the time.
quicklist: 7title: iPhone 5C text: Blue, green, pink, yellow and white -- the iPhone became a fashion statement with the September 2013 release of the 5C.
The most colorful iPhone yet came at an affordable price point while still packing all of the features consumers expected from Apple.
The 5C included even better battery life than its ancestors, a new FaceTime camera a significant iOS upgrade.
quicklist: 8title: iPhone 5Stext: Announced at the same time as the 5C, the 5S was billed by Apple as "the most forward-thinking smartphone in the world."
The device includes an A7 chip, delivering a 64-bit desktop quality experience that can be held in the palm of the user's hand.
It also made its users feel a little like James Bond. The phone comes with Touch ID, a security feature which allows users to unlock their phone and approve app store purchases with the touch of their finger print.