Denver-based Plink, which develops a Facebook-based loyalty program for restaurants and other retailers, has tied with online gift card service Tango Card, the two said this week. According to the two, the move will allow Plink members to earn rewards which can be redeemed at stores such as Amazon.com, The Gap, Home Depot, iTunes, and others. Plink said the move is an expansion beyond its current use of Facebook Credits. The two also said that Plink users will also be able to earn rewards through Tango Card beginning next month, when they shop at dining and shopping partners. Financial details of the partnership were not disclosed.