Google is forcing all developers to adapt their apps to Android 9 Pie or higher. The rule will be in the Play Store in August for new apps, and in November for updates to existing apps. The company will also issue notices to APKs distributed at third-party stores, such as Xiaomi, Huawei and Baidu.
The idea is to prevent developers from looking at older versions of Android as a way to circumvent rules. For example, since Marshmallow 6.0, apps have to ask for their permission before they access the microphone or its location. Spyware applications look at earlier versions, such as Lollipop 5.0, so they do not implement this.
From now on, it will be more difficult. Starting in August, new apps in the Play Store will have to look on Android 9 or higher. And as of November, the rule will extend to the updates.
Will apps continue to be compatible with older versions of Android? Yes! For example, an app may require Lollipop 5.0 as the minimum version, and have Pie 9.0 as the target version. This means that the developer will be required to support modern features such as permissions and notification channels that will be active on compatible smartphones.
Remember that as of August, the Play Store will also require every app – be it a new one or an update – to have a 64-bit version. They can still be distributed in 32 bits.
Xiaomi and Huawei apps stores will require Oreo support
And outside the Play Store? In China, Xiaomi, Huawei, Oppo, Vivo, Baidu, Alibaba and Tencent stores will require apps to look on Android 8.0 Oreo or higher over 2019.
In addition, in August, Google Play Protect will display an alert for users attempting to install an APK targeting an earlier version of Android. For example, if you are in Oreo 8.0, a warning will appear if the app looks in Nougat 7.0 or earlier. Whoever runs Marshmallow 6.0 will be notified if the app looks in Lollipop 5.0 or earlier, and so it goes.
In November, the same rule will apply to updates of already installed APKs. From 2020 onwards, Google Play Protect will require support for newer versions of Android.
With information: Google.