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How Do I Adjust The Touch Screen Vibration (Haptics) On My MetroPCS SCH-R720 (Admire™) Phone?
Haptic feedback causes the mobile device to vibrate when pressing onscreen keys or with certain UI interactions.
Press Home button > Menu button >Settings > Sound settings > Haptic feedback.
Note: Touch the feature to enable it. (If a green checkmark appears to the right of the feature, it is already enabled.)