IDEM Key Plus is a USB security key that provides Web PKI authentication capabilities using x.509 certificates. The device supports NFC connectivity for mobile authentication on both iPhone and Android platforms through provided SDKs. The product offers three integration approaches for different use cases. The plug-and-play Web PKI option enables direct browser access without requiring middleware or proxy agent installation, working across Chrome, Edge, Safari, and Firefox browsers. For mobile applications, developers can use the NFC-enabled SDK to build or enhance apps with secure authentication. Legacy PKI systems can integrate using PKCS#11 middleware on Windows or Mac platforms. The device includes touch verification for user presence confirmation during authentication. The Web PKI technology addresses browser compatibility issues for x.509 certificate functionality without requiring end users to download or install additional software. IDEM Key Plus is designed for organizations that need to integrate PKI-based authentication across web applications, mobile apps, and existing legacy systems. The device supports standard PKI infrastructure while providing modern browser-based access methods.