According to Business Insider, it's the phone's 3D Touch feature that really makes it stand out from other variations of the iPhone. That means that it detects pressure from your fingers, which changes how the phone operates. For example, a light touch on an app will allow you to "peek" into it, while a harder push will open the entire app. That concept allowed app developer Simon Gladman to create an app that could "weigh" small objects using just your cellphone.
Simon created the app to show how the iPhone was able to detect weight using the percentage of the phone's maximum force. For example, a small plum may be 20% if the total force of the phone, and a larger one might be 25%. (Simon originally tried to do this experiment with grapes, but found them too light for the phone to detect.) Check out the video below to see for yourself:You might not use the iPhone 6S as a substitute for a fruit scale (if that's even a thing you use ever) but it is a perfect example of how the iPhone's technology is evolving. Who knows what crazy ish Apple will come up with in the future?