We were the first company in the world to release a range of iPhone 6s and 6s plus cases, and our designs were based on the iPhone 6s dummy which we acquired several months ago, and unsurprisingly the our dummy matches the exact dimensions Apple revealed on their website.
Apple officially introduced the new iPhone 6s & iPhone 6s plus on Sep 9, while both appear to be identical to their predecessors they differentiate themselves from iPhone 6 and 6 plus in terms of hardware and software features along with change in the dimensions. (*Please see image below for dimension comparison)
[*Screenshot - Apple.co.uk]
The new iPhone 6s and 6s plus are heavier, thicker and bigger than its predecessors as confirmed by Apple, so will your existing iPhone 6 case fit the new iPhone 6s?
As mentioned above, our range of iPhone 6s cases were designed inline with the dummy in hand which matches the exact dimensions revealed by Apple that eliminates the question of compatibility issue with our iPhone 6s range.
We have already tested a large amount of iPhone 6 cases from major manufacturers with the dummy iPhone 6s and noticed that only a very small amount of cases are very hard to fit, and once fitted it is very hard to remove. Some cases we have tested just refused to get around the iPhone 6s dummy (ultra slim wrap cases), therefore you may need to wait until you receive your new iPhone 6s to test it for yourself if the case you currently have is one of the ultra slim wrap style cases, or alternatively only opt for cases which are confirmed to fit the new iPhone 6s by checking manufacturer sites.
Please see images below of side by side comparison of an iPhone 6 and iPhone 6s & 6s plus dummy in Rose Gold: