You know that one friend you have? The one who remembers your birthday without a Facebook reminder, who knows exactly how you take your coffee, and sends you songs that somehow are the perfect soundtrack to your life? Now, what if you could make your customers feel the same way about your brand. Sounds impossible, right? Not in the age of social media. In this article, we're going to show you how retailers can use social media not just to sell, but to build a customer loyalty program that feels like you're shopping with a friend who knows you inside