The LG smartphone's call settings allow you to vibrate the device briefly when the call ends.

Android 9 | LG UX 9.0
Step 1:  Open the  Phone -App
Step 2:  Open the  Menu
Step 3:  Tap on  Call settings
Step 4:  Tap on  Additional settings
Step 5:  Enable or Disable  Vibrate when call ends
  1. Open the Phone-App
  2. Open the Menu
  3. Tap on Call settings
  4. Tap on Additional settings
  5. Enable or Disable Vibrate when call ends

LG Instructions