Android Oreo is the eighth major release and the 15th version of the Android mobile operating system. It was released to the public on August 21, 2017.
It contains a number of major features, including notification grouping, picture-in-picture support for video, performance improvements, and battery usage optimization, and support for autofillers, Bluetooth 5, system-level integration with VoIP apps, wide color gamuts, and Wi-Fi Aware.
Android Oreo also introduces two major platform features: Android Go – a software distribution of the operating system for low-end devices – and support for implementing a hardware abstraction layer.
As of October 2020, 16.41% of Android devices run Oreo, with 5.98% on Android 8.0 (API 26) and 10.43% using Android 8.1 (API 27).
Android 8.1 is behind Android 10, by now the third still popular version.