In iOS 10 widgets will be seen on the homescreen and can be accessed via 3D touch feature. Whereas, Android N notifications are much easier to read, have smaller fonts and can be grouped together based on apps.
iTunes brings simplified and easier to navigate interface. Whereas, Play Music allow users to stream music and play downloaded songs. Hence, Play Music cares about its music fans.
iOS Photos app uses machine learning to identify people and objects, and allow users to sort and search photos according to those parameters. It automatically creates slideshows and videos of your best pictures. Whereas, Google Photos app has been doing this over an year and we can say that Apple is just catching up with Google.
Updated iMessage has been introduced with animations, new emojis and now user can also add handwritten messages. Whereas, Google introduces a messaging app called Allo which incorporate search and machine learning technology. The app will also learn over time and suggest replies based on users searches.
Siri vs Google Now
Siri can access third party apps which are not made by apple. Whereas, Google Now has its own voice assistant software and still does not offer this.
Both platforms are a great addition to space. We wont know which OS is more complete and forward-thinking until we get our hands on final software. But there is a fair chance they will function more similar than ever.