I want to do something similar to the picture in picture that appears on the receiver, even when the application is closed, but that would support older versions of Android. With a short googling, I learned about some kind of "overlay" that exists since SDK 23, but when I try to find out in more detail, Google only gives information about the correction of the "overlap detected" error. How to create this overlay?

    1 answer 1

    All the necessary information was here https://habr.com/company/skbkontur/blog/243063/ If briefly, then using android.permission.SYSTEM_ALERT_WINDOW, you can create a WindowManager with View inside on top of any application.