Yubikey OpenPGP card functionality can be programmed with the DidiSoft.Pgp.Smartcard.SmartcardKeyStore class and the low-level cryptography operations are executed on the Yubikey drive.
Other OpenPGP smart cards
The same smartcard OpenPGP API is usable with all OpenPGP smartcards that conform to the OpenPGP smartcard standard version 2 and above, like Nitrokey, and other brands.
DH/DSS keys with 8192-bit encryption key
The newest version of the library now can generate ElGamal (DH/Diffie-Hellman) encryption subkeys with 6144 and 8192-bit size.