Apple unveiled the iPhone 4S Tuesday, a major upgrade over its previous iPhone 4 model, with iOS 5, iCloud and Siri.

The iPhone 4S also marks the first time that Sprint gets to carry the iPhone, joining AT&T (NYSE:T) and Verizon Wireless as the three U.S. carriers to sell the hallowed handset.

The iPhone 4S will be available Oct. 14 in the United States, Australia, Canada, France, Germany, Japan and the UK. The phone will cost $199 for 16GB of storage, $299 for 32GB and $399 for the 64GB model.

iCloud is also a huge part of the iPhone 4S' appeal, allowing users to access their music, photos, apps, contacts, calendars, documents via the Web and sync them across their iPhone, iPad, iPod touch, Mac or PC.

The highlight of the day was Siri, the in-built voice recognition software. iPhone 4S's new feature, Siri, is touted as an intelligent assistant that helps you get things done just by asking.

The iPhone 4S with Apple's A5 dual core processor (as in iPad 2) will be seven times faster than the iPhone 4. Its camera resolution and sharpness have been nearly doubled. Among the most touted feature of the 4S is its 8-megapixel camera, which performs better in low light than the iPhone 4 and offers more vibrant colors.

Apple showed off more than 200 new features in iOS 5, the company's latest mobile operating system. iOS 5, which boasts major Twitter integration, will be available on Oct. 12 as a free software update via iTunes 10.5 for customers who own an iPhone, iPad and iPod touch.

We believe that over time, all handsets will become smartphones, said Tim Cook, the new Apple CEO who took over from Steve Jobs in August.