Want a hint at what's coming in the next iPhone? A good place to look is the invitation to its launch event that Apple sent out Monday:
What's up with all those blurry dots?
My informed guess: The iPhone 7 will be all about improvements to the camera.
That blur effect you see in the invitation is similar to the out-of-focus effect called bokeh. You usually see that effect in DSLR cameras, but there are only a few smartphones like Huawei's P9 that are able to create the look of the bokeh effect thanks to dual lenses on the camera.
And that's exactly what the iPhone 7 Plus model is expected to have. According to numerous leaks, the Plus model will have a dual-lens camera that takes two images at once.
It could also be used to create that bokeh effect. If we had to guess, Apple is going to spend a lot of time talking about the improvements to the iPhone 7 camera since the rest of the phone isn't expected to change much from the iPhone 6s.