THE GOOD Improved speed everywhere(new processor, faster wireless, quicker Touch ID sensor); a sturdier body; better front and rear cameras; a bold new 3D Touch pressure-sensitive display that could end up being a really useful tool in apps down the road, and which already offers new iOS shortcuts.
THE BAD Same battery life as the iPhone 6. The 6S Plus model remains the only way to get optical image stabilization for photos and video, plus better battery life. You’ll need to pay extra to vault past the too-small storage of the entry-level 16GB version.
THE BOTTOM LINE The newest iPhones are top-to-bottom better phones with lots of enhancements; iPhone 6 owners don’t need the upgrade, but everyone else should seriously consider it.