The iPhone 6S and 6S Plus hasn't hit the market yet but word around is that whatever improvements the device carries may likely be a benchmark to what the next iPhone 7 will have to offer.
At the moment, the world is awaiting the release of the iPhone 6S which is expected to be out by the last quarter of 2015. And with reports that Apple is planning to follow a new strategy where they would cut the time frame for releasing new devices at half a year, that could mean that the iPhone 7 could come out somewhere between March to June of 2016.
The iPhone 6S or 6S Plus is expected to be offered for folks who want to get an upgrade although the specs could have minimal changes. However, they could be coming out with better processors (said to be the A9 processors), 4GB of RAM and a curious Force Touch feature.
These features are expected to be carried on to the iPhone 7 which are still expectedly held under wraps. Hence for now, all leaks coming out about the iPhone 7 are purely speculative and unreliable.
Among those unofficial guesses include a possible smaller display size (4-inch), wireless charging capability and likely to boost storage capacity for the benefit of future owners.
From all indications, the iPhone 7 will most likely carry changes on the outside. Internally, it is expected to pick off from what the iPhone 6S and 6S Plus has to offer so it would be safe to say that its borderline specs would be more or less set at that level.
A smaller display could make sense since Apple could consider the success of previous models (like the iPhone 5S) which offered the perfect screen size overall since it could be easily carried and stored anywhere.
A smaller screen size can also render better graphics and of course take a load off the battery when you think about bigger screens trying to render high resolution graphics on a wider scope.
Again, these are purely speculations on what the iPhone 7 could bring. Apple is mum at the moment but expect them to start coming out with teasers once the iPhone 6S and 6S Plus are already out in the market.