Happiness+cities, a local mobile internet entrepreneurship project tailored for cities on three or four lines, was officially launched in 2014 by creative interconnection and, after two years of development, has successfully partnered over 500 regions worldwide (9 overseas cooperation regions). The platform's operational categories include the distribution of the ap platform to the city, the local o2o platform, the o2o comptoir system, the local information app, the forum's social app, the second-hand app, the rental of houses, the job-seeking app, the city-scathing, and the local user service needs, such as telephone calls. Differentiated competitive advantages are achieved through localized operations and services. Happiness+cities is a locally adapted mobile internet entrepreneurship project designed for three or four-line cities. After three years of development, it has become an intra-industry entrepreneurship project. “ham + city” precisely locates the 3-4-5-line cities and county areas, encompassing all local residents' hf and low-frequency demand, combining mobile internet, deep-spreading local living services, and tightening market gaps, bringing together city demand into a large and growing market。