Triple tap to zoom on Android is an accessibility feature which lets you zoom in and out as you tap the screen 3 times. To disable and turn off triple tap to zoom, do as follows:
1. Open Settings application
2. Under System settings, go to Accessibility menu. (On some devices you may change tab, or you may find it under Personal settings)
3. Tap Magnification Gestures.
4. Make sure to turn it off, otherwise you can Pan or Adjust zoom level by tapping the screen, as described in the menu