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I know you have figured it out, but this is for others who do not know how to use a promo code, or what a promo code is.

What is a Promo Code?

A promo code is a code used to get an app that usually would cost money free.

How do I get a Promo Code?

Simple. The Creator of the app has to give it to you. Usually they arent givin away for no reason, but given to people who do app reviews on youtube or post good reviews on i
Tunes.

How do I use a promo code?

The same way you use an iTunes gift card. On the the homepage of iTunes. click "Redeem" Then type in the promo code.

good Luck people.
 
Unless you're running it on your iPod touch or iPhone, then you click the featured tab and scroll to the bottom to find the redeem button.
 
I've been having a problem recently where I try and enter promo codes on my iPhone, it takes the code, tells me I need to be logged in, I log in and it doesn't download the app. Anyone else? This was on 3Gs with iOS 4.02 and now 4.1
 
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