Merchant Customer Exchange (MCX), a consortium of leading US retailers that includes Wal-Mart and Target, is set to run a trial of its mobile payment service – three years after it first announced its intention to offer such a service.

MCX will run the trial at several member retailers and restaurants in Columbus Ohio in coming weeks, said The Wall Street Journal.  The consortium was set up in August 2012.

The news comes as an exclusivity agreement between MCX and its members ends this week, leaving its members free to support rival mobile payment services.

Earlier this week drug store chain Rite Aid, a MCX member, said it will start to support Apple Pay, as well as Google Wallet, from later this month. The drug store said it will back MCX’s CurrentC app when it becomes available, but will also offer customers a range of other options.

CurrentC faces a pack of rivals, including Apple Pay, Google Wallet, as well as the forthcoming Android One and Samsung Pay.

MCX’s app faced some tricky obstacles in bringing CurrentC to market, including the complexity inherent in developing any mobile payment service. However, former employees say an additional burden came from a consortium that includes rivals with conflicting strategies.

CurrentC takes a different approach to rivals because one of its main objectives (shared by all MCX members) is to cut out credit cards (and their costly fees) from its service.

Instead of linking a credit card to its wallet, CurrentC users are supposed to link direct to their bank accounts, gift cards or private label debit or credit cards.

MCX has been testing the app with its members’ employees, including Target and Darden, a restaurant chain, which will begin trialling CurrentC at one of its sites in Orlando, Florida.