Diia (Дія) is Ukraine's unified government platform that offers digital public services and digital documents accessible via a mobile app and web portal. It functions as a "state in a smartphone," allowing citizens to authenticate themselves, use digital documents with the same legal validity as physical ones, and access various government services easily. Services include obtaining COVID certificates, registering vehicles, applying for pensions and social benefits, opening businesses, obtaining licenses, and many others. The platform also supports digital signatures and provides centralized access to multiple administrative services tailored for convenience and efficiency. Beyond individual services, Diia is part of a broader government initiative including "Diia.Vidkryti Dani" (Open Data Center) and "Diia.Cyfrova Hromada" (Digital Community) to promote transparency, open data, and digital transformation in Ukraine's public administration and local governance. Diia is maintained by the Ministry of Digital Transformation of Ukraine and has millions of users, positioning Ukraine as a leader in digital government services worldwide.