There is described a personal communication apparatus (10), for example a mobile telephone, for generating a verifiable recording of a transaction (240), the transaction (240) comprising an exchange of information. The apparatus includes a receiving component, a protection component, a memory and a recording component. The receiving component is capable of receiving a transaction between a user (100) of the apparatus and a remote person, and of receiving biometric data (BIOKY) of the remote person. The protection component is capable of protecting the voice conversation with the biometric data (BIOKY). The recording component is capable of recording the transaction protected with the biometric data on the memory (30). There is also described a communication apparatus (10), which may be the same mobile telephone, operable to support authentication of a transaction therein. The communication apparatus comprises a memory (30) and an authentication component. The authentication component is capable of providing access to a protected transaction stored on the memory if biometric data (BIOKY) measured by a biometric measuring means (80) corresponds to earlier biometric data (BIOKY) used to protect the voice conversation (240).