Question: how do i set a custom ringtone on my android?
Answer: Open Settings.
Tap the Sounds section. ... 
Tap Phone ringtone. ... 
If you get an "Open with" or "Complete action using" prompt, select the system's Sound Picker app instead of a file manager or Zedge.
Tap the custom ringtone you added to the ringtones folder.
Tap Save or OK.