China is facing the rapid development of digital technology torrent and the increasingly serious aging population problem, the development of technology has led to a digital economy and cashless society. While people conveniently carry out economic activities through digital means, social problems such as network fraud, theft of others' privacy, digital divide and other social problems have gradually become prominent. Older people are more likely to fall victim to digital isolation and online fraud due to their ability (especially cognitive ability) decline and behavioral fixation, derailment from the experiences learned in the cash society, and lack of appropriate digital citizenship education. Starting from the concept of service design and starting from the current situation of the demand of people aged 50-70 (referred to as the new elderly people), the content framework of the new elderly people in the era of digital economy is summarized, and a sustainable knowledge service system of "people-contact-environment" interaction is constructed with mobile applications as the carrier.

Xin Zhao, Dan Liu. Based on the new old crowd digital currency consciousness Design of knowledge service system. The Frontiers of Society, Science and Technology (2021) Vol. 3, Issue 6: 63-67. https://doi.org/10.25236/FSST.2021.030610.

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