An apparatus, comprising: - a screen; - a non-secure zone; and - a secure zone comprising: - a non-volatile storage configured to store at least one digital certificate and at least one encryption key, the at least one digital certificate comprising information representing a task signer; - a secure hardware processor configured to execute a task associated with the at least one digital certificate; and - a supervisor implemented using at least one hardware processor configured to: - control access to the at least one digital certificate and the at least one encryption key; - assume control over an output of the screen when the apparatus operates in a secure mode, wherein the secure mode is a first secure mode or a second secure mode; - wherein when the apparatus operates in the first secure mode the supervisor is configured to: delegate control of a first portion of the screen to the task executing on the secure hardware processor, and display in a second portion of the screen the information representing the task signer from the at least one of the digital certificate; - wherein when the apparatus operates in the second secure mode the supervisor is configured to: delegate control of the entire screen to the task executing on the secure hardware processor; and - wherein when the apparatus operates in a non-secure mode the supervisor is configured to transfer control over the output of the screen to the non-secure zone. - a screen; - a non-secure zone; and - a secure zone comprising: - a non-volatile storage configured to store at least one digital certificate and at least one encryption key, the at least one digital certificate comprising information representing a task signer; - a secure hardware processor configured to execute a task associated with the at least one digital certificate; and - a supervisor implemented using at least one hardware processor configured to: - control access to the at least one digital certificate and the at least one encryption key; - assume control over an output of the screen when the apparatus operates in a secure mode, wherein the secure mode is a first secure mode or a second secure mode; - wherein when the apparatus operates in the first secure mode the supervisor is configured to: delegate control of a first portion of the screen to the task executing on the secure hardware processor, and display in a second portion of the screen the information representing the task signer from the at least one of the digital certificate; - wherein when the apparatus operates in the second secure mode the supervisor is configured to: delegate control of the entire screen to the task executing on the secure hardware processor; and - wherein when the apparatus operates in a non-secure mode the supervisor is configured to transfer control over the output of the screen to the non-secure zone. - a non-volatile storage configured to store at least one digital certificate and at least one encryption key, the at least one digital certificate comprising information representing a task signer; - a secure hardware processor configured to execute a task associated with the at least one digital certificate; and - a supervisor implemented using at least one hardware processor configured to: - control access to the at least one digital certificate and the at least one encryption key; - assume control over an output of the screen when the apparatus operates in a secure mode, wherein the secure mode is a first secure mode or a second secure mode; - wherein when the apparatus operates in the first secure mode the supervisor is configured to: delegate control of a first portion of the screen to the task executing on the secure hardware processor, and display in a second portion of the screen the information representing the task signer from the at least one of the digital certificate; - wherein when the apparatus operates in the second secure mode the supervisor is configured to: delegate control of the entire screen to the task executing on the secure hardware processor; and - wherein when the apparatus operates in a non-secure mode the supervisor is configured to transfer control over the output of the screen to the non-secure zone. - control access to the at least one digital certificate and the at least one encryption key; - assume control over an output of the screen when the apparatus operates in a secure mode, wherein the secure mode is a first secure mode or a second secure mode; - wherein when the apparatus operates in the first secure mode the supervisor is configured to: delegate control of a first portion of the screen to the task executing on the secure hardware processor, and display in a second portion of the screen the information representing the task signer from the at least one of the digital certificate; - wherein when the apparatus operates in the second secure mode the supervisor is configured to: delegate control of the entire screen to the task executing on the secure hardware processor; and - wherein when the apparatus operates in a non-secure mode the supervisor is configured to transfer control over the output of the screen to the non-secure zone.