Supplementary information: My Yancheng is a government life service app specially built for the citizens, and it is the gateway to Yancheng's smart city construction. Provide government affairs, health care, transportation, social security, wisdom education, real estate services, public services and other services, so that citizens can easily handle all kinds of government affairs without leaving home. My mobile phone Yancheng app Social Security verified payment is a convenient service software launched by Yancheng Municipal Party Committee and Municipal Government, and all relevant information of Yancheng is available here. Users can easily understand the surrounding life service areas by using the app, and they can also understand the local history and culture in the software and easily integrate into the lives of local people.