A significant change in iOS 10 is that you must declare ahead of time any access to private data or your App will crash. Private data is one of these: Contacts, Microphone, Camera and more. This post has all the details.
Source: Privacy Settings in iOS 10
I few months ago I started reading about Neural Networks and Machine Learning algorithms in general. At WWDC 2016, Apple introduced two neural network APIs, called Basic Neural Network Subroutines (BNNS) and Convolutional Neural Networks (CNN). An interesting move in my honest opinion. Read this one for more information.
Source: Neural Networks in iOS 10 and macOS | Big Nerd Ranch