There are some advantages. Let us that your phone has 500 MB internet with just two days left in the period validity . When you buy the package will extend to another. But the packages of 4 mb internet valid only for two days. To increase your mb validity generally you have to buy 75 mb internet pack by 25 taka . But with Flexyplan you can pick up 4 mb internet with 30 days validity just in 1 ( One ) taka !! It save the money.
You can also send internet pack / talk time / sms to othere. This means that you can send internet pack / talk time / sms to friends or Daddy (I sometimes do this) .
How to Buy a internet Pack or sms or talktime with GP Flexi Plan :
At first go to any phone or PC's browser Sign in http://www.grameenphone.com/flexi-plan this link. It will appear as like as the image given below. Which you want choose and click on this to Select. Then click on the BUY NOW option for byeing the pack made.