UK antitrust authorities said they plan to investigate Apple Inc.’s App Store to probe whether it is abusing its market power to restrict competition. The Competition and Markets Authority said it plans to investigate Apple’s potentially “dominant” position in the supply of apps on iPhones and iPads. “Complaints that Apple is using its market position to set terms which are unfair or may restrict competition and choice – potentially causing customers to lose out when buying and using apps – warrant careful scrutiny,” Andrea Coscelli, who leads the CMA said in a statement Thursday.