It is still not known how customers will receive Apple's latest device, iPhone 6s, when it hits the stores. The response is expected to be not as good as its predecessors if the performance of the company's stocks ahead of new device announcement is any indication.

Investors clearly conveyed their scepticism about iPhone 6s and 6s Plus by bringing down Apple shares. However, the stocks picked up after the release of the devices.

Both investors and Apple fans have their reasons to be upset with the new device and the mistake should not be repeated in iPhone 7.

[Read: Apple's iPhone 6s Gets Cold Response From Investors]

It is common knowledge that iPhone 6s is just an upgraded version of iPhone 6. There is no noticeable difference between the two devices from looks to specifications except the 3D Touch technology.

The fact is, Apple devices have become so predictable over the years that many may have stopped expecting novelty from them. As expected, iPhone 6s did come with some improvement in both hardware and software, but they are not something that's worth the hype and wait. The new phone is heavier than its predecessor by 14 g, thicker by 0.2 mm, and has a smaller battery, which many gadget lovers will not like.

The Cupertino-based giant should win the hearts of its fans and attract new users with its upcoming device dubbed as iPhone 7. But it is clear by now that a few feature upgrades are not enough. So, there has to be innovation from looks to specifications in the future iPhone.

Nothing about Apple's upcoming device is clear as of now but reports have suggested that it will come with a major overhaul. It could be the slimmest iPhone ever, measuring between 6.0 and 6.5 mm, may have a camera with six-element lenses, and without its iconic Home button. There are also reports that it will be powered by A10 chips and run on a new iOS.

The device is expected to be released in September, 2016, by the time its predecessor, the iPhone 6s completes one-year cycle in the market.

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