Apple has announced the iPhone 6S and iPhone 6S Plus at an event in San Francisco. The two new iPhones won't come as too much of a surprise, with many expecting them, but there were a few more features added than normal, given we are in an S year.

The company claimed the new iPhones "may look familiar but we have changed everything". In light of this, we have compared the iPhone 6S Plus to the iPhone 6 Plus to see what the differences are and what Apple has changed.

The Apple iPhone 6S Plus and the Apple iPhone 6 Plus are almost identical in design. As we mentioned, it is an S year so this was to be expected. Apple did opt for a different grade of aluminium in the new device, and introduced a new colour - rose pink - so there have been a couple of slight design changes.

The new 7000 grade aluminium is the same material Apple used on its Apple Watch. It is said to be stronger but lighter than what the iPhone 6 Plus is made from so hopefully that means the end of any more bendgate incidents.

The iPhone 6 Plus was the device that took Apple into phablet territory with its 5.5-inch display. The iPhone 6S Plus sticks with the same size, but it features what Apple is calling 3D Touch. You can read all about the technology in our dedicated feature, but in a nutshell, a hard press will deliver a different level of interaction. For example, holding down the camera app icon will bring up what Apple calls a Peep, which is a menu offering easy access to various features such as the selfie camera.

Both the iPhone 6S Plus and the iPhone 6S feature Full HD resolutions at 1920 x 1080, which means a pixel density of 401ppi. This is lower than the competing devices at this size, but the iPhone 6 Plus display was still good, so we'd expect the same from the iPhone 6S Plus.

Some thought the resolution would see a bump in the new device but this wasn't the case for the iPhone 6S or iPhone 6S Plus.

The iPhone camera has seen a lot of praise over the last few years. It may not have as many megapixels as its competitors, but the iPhone 6 and iPhone 6 Plus are still able to take very good smartphone shots.

The iPhone 6S Plus does up the megapixels however, bringing it a little closer to other devices in its market, though still not on par. The iPhone 6S Plus will come with a 12-megapixel rear snapper and a 5-megapixel and Apple claims the iPhone 6S Plus will take better pictures than the iPhone 6 Plus.

The iPhone 6 Plus by comparison features an 8-megapixel rear camera and a 1.2-megapixel front camera so there should be noticeable improvement with the new device.

The iPhone 6S Plus will also come with a new feature called Live Photo. When you take a picture, the iPhone 6S Plus will automatically capture 1.5-seconds previous to the shot being taken and 1.5-seconds after. You will then be able to "play" the image when you look at it on any Apple device, allowing you to relive the moment it was taken in, like the cars going past or the ripples in water.

The iPhone 6 Plus features the A8 processor and M8 motion coprocessor, while the iPhone 6S Plus has the new A9 chip with a integrated A9 motion coprocessor. According to Apple, the new processor means the iPhone 6S Plus will be 70 per cent faster in terms of CPU and 90 per cent faster in terms of GPU than the A8 so you can expect a performance improvement.

Both the iPhone 6S Plus and the iPhone 6 Plus are available in 16GB, 64GB and 128GB storage options, none of which offer expandable storage via microSD. They are also the same price.

Apple always debuts its new iOS software on the latest iPhone, which means the 6S Plus will feature iOS 9 and all the new features. The iPhone 6 Plus will get the update to iOS 9 however, so there will be no difference in software experience between these two devices.

Apple's iOS 9 will bring improvements to Siri, search and Maps, as well as change the name of Passbook to Wallet, among other features.

The Apple iPhone 6S Plus makes several improvements over the iPhone 6 Plus, including colour choice, display technology, camera and processor.

All the changes are mainly on the inside, but there are a few exciting additions on the iPhone 6S Plus that makes upgrading more justifiable.

The iPhone 6 is a fantastic device but the iPhone 6S Plus is the winner in terms of the numbers and the extra tech.