The mobile channels we are using to access information, communicate with others, and buy products enrich the implementation of omnicahnnel retailing. The aim of this dissertation is to understand consumer shopping behavior in mobile channels of a multichannel system offered by a retailer. The first study reveals a strong disparity between the practice of multichannel/omnichannel retailing and the relevant research, especially with regard to consumer behavior in mobile channels. The second study focuses on app adoption’s effect on customer shopping and demonstrates that, it is worth investing in a app for retailers because customers who use the app show a higher possibility to purchase products and have higher actual spending, even the customers had shopped in a very similar channel (i.e., mobile website) before. Moreover, a shopping app, compared to a mobile website, is able to mitigate consumers’ perceived risk and enhance customers’ loyalty. The third study discusses a discount strategy implemented by online retailers in China, which also happens in other areas. That is, some small and medium-sized online retailers are providing deep discounts in digital channels all the time to fight for customers and market shares from digital giants (e.g., Alibaba Group and JingDong.com). However, providing a long-term and deep discounts is not a fully successful strategy, since we find that such a strategy only works on attracting customers to purchase more but leads to profit loss at the end.