Google has several forward-looking changes to Android planned, the effects of some will be felt soon while others will make a difference later.
Starting in August 2018, new apps will be required to target Android 8.0 API. They can still support old versions of Android, but theyll have to play by the rules when running on Oreo and later.
This makes some currently optional features mandatory like using Marshmallows runtime permissions. Additional requirements will improve user privacy while limiting the performance impact of ill-behaved apps.
From November 2018, not just newly-added apps but also app updates will need to play nice with Oreo. And as the years go by, the target version will be advanced to prevent old apps from anchoring phones to the past.
Also in 2019 (August specifically) apps will be required to support 64-bit chipsets. They can still run on 32-bit hardware, but this is in preparation for a 64-bit only future. Apple already made that switch with iOS 11, but Android supports a mind-boggling number of platforms so it needs more time.
In 2018, the Google will help improve security by adding small bits of security metadata to apps downloaded from the Play Store. It will serve as a batch of authenticity and will enable new distribution opportunities for developers… whatever that means.