System notifications are one of the most feature-rich and API fragmented parts of Android. In each new version of OS we receive new functions for creating notifications, which allow us to receive information from the user without entering the application and quickly interact with him. The most interesting thing is that some functions replace others.
How to use all possibilities of the notification system to the max? How to make a notification on each OS? NotificationCompat will not decide everything for you. Let's dive into this!