Android: Use "Home2 Shortcut" app to replace "S Voice" with Google Now (Voice Search)

Do the following to start Google Now Voice Search instead of S Voice on your Samsung Galaxy mobile phone by double pressing the home key quickly:

+ Install "Home2 Shortcut" from the "Play Store" app

+ Open "Home2 Shortcut" app

+ Tab on Choose Application button, select Installed Applications and then choose "Voice Search" app as the start application. Click OK button

+ Choose Home Application: TouchWiz home from Samsung

+ Tab on the Close button. Set "Home2 Shortcut" app as default if there is any pop-up window to complete this action

+ Open "S Voice" app, press the menu key, select Settings, untick the box next to "Open via the home key, Open S Voice by double pressing the home key", and then close the S-Voice app by pressing back key multiple times

+ Open "Google Now Voice Search" app, press the menu key, select Settings, select Voice, tick the box next to "Hotword detection", and then close the Voice Search app by pressing back key multiple times

+ Connect to the internet through WiFi network

+ To test, double pressing the home key quickly to open Google Now Voice Search instead of Samsung S-Voice. Say "OK Google" to launch voice search. Enjoy telling Google Now Voice Search app what to do. For example, say, "OK Google, call Mars", assume that Mars is in your phone contact list.

Caveat:
Do not use "S for Switch Voice" app. Use "Home2 Shortcut" app instead.
Stop putting more Samsung applications to the Samsung Android smartphones.