A word of caution though: when you are applying this fix, do not exert too much pressure as you might end up breaking the hardware inside the charging slot. All it needs is a gentle push.
The Charger Fix
You need to watch this video to understand the iPhone home button charger fix for iPhone 4, 4S, 3, iPad and iPod Touch. All credits to iPhone4idiots on YouTube. Thanks guys!
Update: We have used this fix numerous times and we have seen that if your iDevice is getting old, you might need to repeat this fix quite often. To get the best performance from our aging iPhone4's home button, sometimes we use this fix as a supplement to the alcohol fix.