OpenSC is described as 'provides a set of libraries and utilities to work with smart cards. Mainly on cards that support cryptographic operations, and facilitate their use in security applications such as authentication, mail encryption and digital signatures'. There are four alternatives to OpenSC for Windows, Linux and Mac. The best alternative is YubiKey PIV Manager, which is both free and Open Source. Other great apps like OpenSC are Pkcs11Admin (Free, Open Source), Cardpeek (Free, Open Source) and PUPPICAD (Free).