Mobile identity is a development of online authentication and digital signatures, where the SIM card of one’s mobile phone works as an identity tool. Mobile identity enables legally binding authentication and transaction signing for online banking, payment confirmation, corporate services, and consuming online content. The user's certificates are maintained on the telecom operator's SIM card and in order to use them, the user has to enter a personal, secret PIN code. When using mobile identity, no separate card reader is needed, as the phone itself already performs both functions.