h strategy, and marketing. To cope with customer trend changing rapidly and maintain competitiveness with various incompatible technologies is main issue for operators. Especially, in the service development, the value chain of providing mobile data services is much more complex than that of voice services. Therefore the value chain strategy which considers the provision of complementary products and services and the integration of multiple products and services into solutions for customers is a crucial part of the strategies. 13.2.3 Data Collection The data for comparison are collected with a focus on the MNOs. Two Chinese MNOs, China Mobile and China Unicom which were the only two MNOs in China before October 2008, are studied. In the United States, the four nationwide MNOs, AT&T, Verizon Wireless, Sprint Nextel, and T-Mobile have about 87% market share by the volume of subscription. In South Korea, three MNOs-SKT, LGT and KTF compete in the market. Since all the three countries have few major operators cover- ing dominating market share, they are holding real power over the industry. With the infrastructure integrating the value from terminals, equipment, systems, and services, they are the most important hubs and have the strongest influence in the industry. The CPs and SPs are all connected to MNOs. Therefore, in terms of description of business strategy, we expect that operator-centric perspective can be a prism reflecting the general tendencies of various players in the mobile communication industry. 13.3 Performance of Developing Mobile Data Services 13.3.1 Diversity Based on various technologies, mobile data services can support a large number of applications. It results in multiple service categories, and some categories overlap Comparative Study on the Mobile Data Service Development each other. Here we describe the diversity of mobile data services in the three countries from two levels: technological platforms and applications (see Figure 13.1). The former refers to the service providing means to car