The iPhone 6S model which is likely to arrive in September could be three times efficient, thanks to its ARM-based processor the Cortex-A9. Aside from that, it is also rumored to have a far superior Touch ID, dual lens DSLR-quality camera, and a 3D pressure sensor.

Ming-Chi Kuo, a high profile Apple predictions guru and who works as a KGI securities analyst, predicts that the upcoming iPhone S model will have a far superior fingerprint scanner. The analyst is quick to point, though, that the improvement he is talking about could not be the patent on the integration of Touch ID and touch panel that Apple has filed recently.

He warned iPhone users not to hold their hopes too high as the Touch ID will remain embedded in the home button. Challenges like complicated algorithms and other requirements like sapphire cover lens will not make it possible to arrive anytime soon. But it sure is a development in progress that is aimed at reducing reading errors for a safer and better Apple Pay user experience.

The iPhone 6S may also finally receive a boost in RAM. A Taiwanese media hints that being part of Apple's next-generation of iPhone, including the S model, may pack as much as 2GB of LPDDR4 RAM. This will double the handsets' bandwidth without taking its toll on the battery life. But as Digital Trends points out, this is an old promise that keeps on resurfacing every time a new device is coming.

The iPhone 6S is also speculated to use similar two-lens system camera that HTC uses for One M8. This camera set up, according to Apple commentator John Gruber, will allow DSLR quality imagery. The aperture will also be enhanced to let in more light than the normal lens allow.

If Gruber is right, the camera module will no longer stick out - a problem that's causing annoyance to iPhone 6 and iPhone 6 Plus users. By dividing the lens in two the camera module would be trimmed down to fit flush against the handset's thin profile.

There are also speculations about the 3D technology sensor coming to the iPhone 6S. For some it is unclear how it is going to prove useful on the iPhone other than the promise that it could provide a new way of interacting with the device.