Covid-19 has driven us abruptly to a new world of contactless society. It also compelled us to use online shopping, especially mobile shopping in South Korea, where the dominant mode of wireless communication was already 4G services when Covid-19 broke out. This paper examines the different roles of mobile networks and the Covid-19 pandemic in transforming mobile shopping submarkets in South Korea by estimating the long-term and short-term effects of these two factors on mobile shopping sales. We used a cointegration and an error correction model to estimate long-term and short-term effects separately. This paper finds that Covid-19 was a major short-term factor affecting sales in mobile shopping submarkets, while mobile network subscribers were a key long-term driving factor of mobile shopping sales growth.