AUTHADA sign is a digital signature solution that enables users to create Qualified Electronic Signatures (QES) compliant with the eIDAS regulation. It is developed in collaboration with qualified trust service provider InfoCert. The signing process requires identity verification via the AUTHADA app using a government-issued ID and PIN. Once identity is confirmed, users can review documents within the AUTHADA sign interface and sign them with a single click. As an additional security factor, a one-time password (OTP) is sent via SMS to the user's mobile device, which must be entered to complete the signature creation. AUTHADA sign is designed for B2C use cases, where end users sign documents on behalf of service providers (e.g., banks, brokers, insurance companies, telecoms, or online shops) that have integrated AUTHADA sign into their workflows. The QES produced is legally equivalent to a handwritten signature under EU law, making it suitable for documents with statutory form requirements or high liability exposure, such as purchase or credit agreements. No physical printing or filing is required. The solution operates via smartphone and supports two-factor authentication (2FA) as a regulatory requirement for QES issuance.