This article explains how to disable the Google application on your Android device to remove the search bar from the home screen.
Steps
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Step 1. Open the Android applications menu, which lists all the original or third-party apps installed on the device
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Step 2. Tap the icon
to open the settings menu.
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Step 3. Tap Apps in the settings menu to open a list of all applications
This item could also be called "Applications" or something else, it all depends on your device and the software you are using
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Step 4. Tap Google
The icon looks like a colored G in a white circle. Tapping it will open the application information page.
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Step 5. Tap the Deactivate button on the application information page
The action must be confirmed in a pop-up window.
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Step 6. Tap OK to confirm and disable the Google app on your device
You can uninstall the updates, but you cannot remove the Google app from Android
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Step 7. Reboot the device
Turn your phone or tablet off and on again to make sure you apply any changes you have made to settings associated with the application. Since Google will have been disabled at this point, you will no longer see the search bar on your device.