Late last year, Google announced security-focused changes within its Play Store that requires attention from developers by the middle of 2018. With mid-2018 upon us, Google's new policy requires that apps target a recent API (e.g. currently, apps need to target API level 26, Android 8 Oreo). Reports indicate that Facebook is abiding by the changes.
Facebook has announced that its main Android application will target Android 7.1 Nougat in compliance with Google's new policy. To stay in compliance, Facebook will need to update its entire app portfolio to target the same API or newer. To remain in compliance, Facebook will need to target Android 8.0 Oreo by November of this year. Facebook, and all other app developers will need to keep up with Android API updates moving forward.
Google's goal in the new policy is to create a more secure app environment within the Play Store, and to reduce fragmentation across its app ecosystem. Because the entire app community will target a recent API, Google creates a type of standardization. Such standardization will provide some expectation and commonality for how apps interact with the operating system.
Google is changing the game for developers of Android apps and devices. Google pitches the changes as a method to enhance security, performance, and standardization. Time will tell how much burden this places on developers, and how well the policy change will work.