The aim of this study was to identify environmentally and socially sustainable behaviors and explore the role of mobile applications in encouraging them among young residents of Poland. The study involved a literature review and a survey carried out on a sample of 772 representatives of Generation Z (through the use of CAWI method). The collected material was subjected to quantitative and qualitative analyses involving factor analysis and statistical tests. The analysis of the obtained dataset shows that there is a significant difference between pro-environmental behaviors assigned to the following areas: (I) purchasing activity enhanced by visual identification, (II) sustainable consumption, (III) behavior stimulated by legal regulations and economic factors. The research revealed a statistically significant difference between the sustainable behaviors of men and women, and a slight difference between the behaviors of people from different places of residence and with different levels of income. It was also shown that respondents using the three analyzed mobile applications: Vinted (an online marketplace and community that allows its users to sell, buy, and swap new or secondhand items, mainly clothing and accessories), Veturilo (an app for users of city bike system) and GdzieWyrzucić (an app helping with waste sorting) rated their pro-environmental activities significantly higher in almost all areas covering socially and environmentally sustainable behaviors.