While Mophie and the other players in the big case and accessory league may take their sweet time to mark their extended battery cases for the iPhone 6 and the larger 6 Plus as compatible with the new 6s and 6s Plus, smaller manufacturers are already filling the void, and with very enticing propositions at that, most of which can be had right now. After all, the difference in thickness is less than tenth of an inch, so almost all of the cases that fit the iPhone 6, will fit the 6s as well.
The iPhone 6s is a great piece of hardware - fast, with a luminant pressure-sensitive 3D Touch display, and great 12 MP camera quality, but it is marred by one major drawback - its battery life. Apple posted official iPhone 6s battery life specs that are on par with the iPhone 6 before it. However, let's not forget that the iPhone 6 battery life numbers have been posted with iOS 8 onboard. The iOS 9 update brings major optimizations that may squeeze an hour more from your handset, so the true iPhone 6s battery endurance might be even shorter than the iPhone 6, as it ships with iOS 9 onboard from the box, and that's how its official battery life numbers have been calculated, too.
In any case, you'd still have to charge it every day with normal usage, like its predecessor, while some Android flagships are now on the two-day stretch, and even a three day usage on a charge isn't out of the question with some midrangers carrying giant 4000mAh+ batteries. Fret not, though, as there is a rich accessory ecosystem around the iPhones. A simple extended battery case would stick like a spoon on butter to the new iPhone 6s, providing you both with protection, and two-day smartphone-ing out of Apple's finest. Here are a few of those that are currently available, and we will be adding more when they hit the market.