Haha.. I did a google and found out this amazing trick I want to share here!!

Can’t believe it that I’ve been struggling with this unresponsive Home button for months~ just a few weeks after I got my iPhone4, I noticed the Home button wasn’t responding, I had to use my Activator to assign a Double-tap action to perform the App Switcher. At first, I even bought the Home button sticker and ended up making so many outgoing calls unconsciously. If you also have the same problem with me, no harm trying this~?

How I use the Activator

Settings -> Activator -> Anywhere -> Double Tap Status bar -> Activate Switcher.

How to re-calibrate my iPhone Home button

Step 1: Open any stock app, I opened the Weather app.

Step 2: Press and hold your power button until “slide to power off” appears and release.
(Do not instinctively go slide and off your phone ok..)

Step 3: Press and hold your Home button until the “slide to power off” goes away, and the app force quits.

Your iPhone’s Home button should now be more responsive, because it has been re-calibrated.

Credits: iDownloadBlog