You may have accidentally turned 
  TalkBack on when you began phone setup. TalkBack is designed to give voice feedback to those who have visual impairment.If you accidentally turned TalkBack on during phone setup you can turn it off on the choose language screen.
 
- On the choose language screen, draw an "L" with your finger to display TalkBack controls.
- Tap Pause feedback. 
- Tap the OK button, and then double-tap the screen  to suspend TalkBack.
- Tap Accessibility settings. If you don't see this button, you may need to tap  Vision settings or Tools first.
- Tap TalkBack, and then tap  the On/Off switch to turn TalkBack off.
- Tap BACK to return to the language screen.
Note: To find out more about TalkBack, see the user guide or how-tos.