A woman on a street in Seoul checks her cellphone. The government is ramping up efforts to control an outbreak of the Middle East respiratory syndrome by monitoring the smartphones of those under quarantine.
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The sun sets as a visitor uses his mobile phone Monday during the opening day of the 2015 Mobile World Congress in Barcelona. Wall Street Journal reporter Ryan Knutson — interviewed from the conference Monday via Skype by NPR's Robert Siegel — says that for some smartphone users, Wi-Fi may be able to replace most of the functionality of a cellphone carrier.
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