Use APKPure App
Get I'm Busy old version APK for Android
Now just one touch is all you need to get your own busy mode.
Now just one touch is all you need to get your own busy mode. Click on “ On Busy Mode” to disable sound for all incoming calls and messages with auto-reply functionality.
Customising busy message is extremely easy, click on Settings button and replace default “I am busy.” with your own busy message. You can also enable/disable auto-reply functionality for calls and/or messages.