Mobile hack to call your friends:
1. Go to http://www.mobivox.com and register there for free account.
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2. During registration, remember to insert Victim mobile number in "Phone number" field as shown below.
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4. You will arrive at page shown below. In "Enter a number" box, select your country and also any mobile number(you can enter yours). Now, simply hit on "Call Now" button to call your friend with his own number.
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5. That's it. Your friend will be shocked to see his own number calling him. I have spent last two days simply playing this cool mobile hack prank.
How to make a call to your friend with his own number