At last week's Smart City World Expo in Barcelona, Jong-Sung Hwang, former CIO of the Seoul metropolitan government, informed of the city's attempt to capture real-time traffic data. For years the city invested millions of dollars in sensors embedded into the road infrastructure.
"But we failed again and again," said Hwang. "It cost a lot ... but the traffic information was not correct so could not be used." In 2012, however, the city's 25,000 taxis introduced a touchcard payment system using GPS technology, effectively giving Seoul the real-time traffic information it had long craved at a fraction of the cost. "A smart city can now use smart technology and solve problems without changing the city infrastructure", said Hwang.
Good article on how smart cities can be implemented using technologies that are increasingly being deployed for related developments.