We're still a couple of days away from Apple's big iPhone 6s event, but analysts already have one eye on next year's refresh. According to one, the iPhone 7 will come with a brand new form factor that's as thin as an iPod touch.

Next week's iPhone refresh won't bring any major design changes; the iPhone 6s and 6s Plus are expected to look identical to their predecessors, but with big upgrades internally. However, Apple has traditionally introduced new designs every other year.

That means the iPhone 7 is on track to get a brand new look, and reliable KGI Securities analyst Ming-Chi Kuo expects it to be the slimmest Apple smartphone to date, measuring between 6mm and 6.5mm thin.

That means the iPhone 7 could be almost 1mm thinner than the existing iPhone 6, which is already one of the slimmest smartphones on the market. Kuo believes Apple will achieve this by sticking with in-cell display technology.

This contradicts a recent rumor that claimed Apple will shift back to glass-on-glass display technology like that employed by the original iPhone in pursuit of greater resolutions. Existing in-cell panels have limitations when it comes to pixel density, but Kuo believes Apple isn't interested in reaching 4K resolutions with the iPhone any time soon.

It's unclear what kind of impact this form factor would have on battery life, however. Apple would presumably need to make its batteries slimmer, too, and this could mean our iPhones won't last as long in between charges.

We shouldn't be too concerned about this for now, however. The iPhone 7 is still more than a year away, and Apple's plans will almost certainly be revised before then. In the meantime, let's focus on the iPhone 6s and 6s Plus coming this week.