Apple's Chief Executive Officer Tim Cook took to the stage in San Francisco's large Bill Graham Civic Auditorium to announce the new iPhones along with a series of updates to the company's other products including the iPad Pro and Apple TV.
"What we have to show you today is really awesome, While they may look familiar, we have changed everything about these new iPhones," CEO Tim Cook said.
Along with unveiling the iPhone 6S and 6S Plus, Apple revealed a lot of other gadgets including a revamped Apple TV and the iPad Pro. Apple live streamed the event.
This year's iPhone is Apple's off "S" year. That means Apple keeps the basic design of the device the same but adds other features to attract buyers, like the Siri digital voice assistant in the iPhone 4S and the TouchID fingerprint reader in the iPhone 5S.
A marquee feature for this year's iPhone 6S was expected to be the Force Touch technology used in the Apple Watch, a pressure-sensitive display that responds to various types of touches. The company instead unveiled '3D Touch', a feature that appears to have the same capabilities.
The iPhone 6S and 6S Plus will also support LTE Advanced, a faster version of 4G currently supported by EE and Vodafone in the UK and rival manufacturers Samsung and LG.
The new iPhones will also have Wi-Fi calling that can be used when no mobile phone signal is available, which currently supported by EE in the UK.
The standout feature of the new iPhone 6S and 6S Plus is the new touchscreen technology called '3D Touch'.
First introduced with the Apple Watch as Force Touch and then the Apple MacBook trackpad, the pressure-sensitive touchscreen can detect various types of tap. From a single traditional tap to heavier presses, each gesture can produce a different interaction with the smartphone.
"We've fitted brand new glass, the strongest in the industry X-ion and we've improved on multitouch with '3D Touch', a tremendous breakthrough in interacting with the smartphone," said Phil Schiller on stage.
The new 4.7-inch 6S and 5.5-inch 6S Plus, which are the same size as last year's models, will be available for pre order starting Saturday and will go on sale from September 25 in the US, UK, China, France, Japan, Australia among others. The phone will be available in 130 countries by year's end.
Following Apple's typical pricing system, the base-model iPhone 6S will cost USD 649 without a two-year carrier contract. Prices for the iPhone 6 and iPhone 6 Plus will be knocked down by USD 100.


See in pics: Apple launches iPhone 6S, iPhone 6S Plus!!!