If you are using Android Keyboard on your Google Nexus 4, you may have noticed of vibration when pressing keys. To disable keyboard vibration on Nexus 4 do as follows:
1. Open "Settings" and go to "Language & Input"
2. Find "Android Keyboard" and tap the setting icon right to it
3. Unmark "Vibrate on Press" to disable vibration keyboard (To enable this feature, make sure it is enabled)