The UK's Competition and Markets Authority (CMA) is investigating potential action against Apple and Google for their app store dominance, which the Coalition for App Fairness claims costs UK users £4bn annually. The CMA is considering designating the companies as having Strategic Market Status (SMS) to intervene in their mobile ecosystems. The consultation phase, lasting until February 12th, seeks feedback on Apple and Google's market power and influence. If designated with SMS status, the CMA could enforce fair competition rules and potentially require Apple to allow rival app stores on iPhones. The CMA expects to make a decision on Apple and Google's SMS status within nine months.