Methods and systems of securely storing documents on a mobile device

A method of encrypting information using a computational tag, the method comprising:

• by a mobile electronic device, detecting a computational tag within a near field communication range of the mobile electronic device;
• by the mobile electronic device, identifying a document to be encrypted;
• by a storage application of the mobile electronic device, encrypting the document and generating an unencrypted key that may be used to decrypt the encrypted document;
• by the mobile electronic device, transmitting the unencrypted key to the computational tag;
• by the mobile electronic device, receiving, from the computational tag, an encrypted key, wherein the encrypted key comprises an encrypted version of the unencrypted key;
• and
• storing the encrypted key in a memory of the mobile electronic device and not retaining the unencrypted key in the memory of the mobile electronic device.

A method of controlling access to a document, comprising:

• by a mobile electronic device, receiving a request from a user to access an encrypted document;
• by the mobile electronic device, detecting that a computational tag having decryption capability is in proximity to the mobile electronic device;
• transmitting an encrypted object to the computational tag;
• receiving a decrypted version of the encrypted object from the computational tag;
• and
• in response to receiving the decrypted version of the encrypted object, presenting a decrypted version of the encrypted object to the user.

A system of encrypting information using a computational tag, the system comprising:

• a mobile electronic device;
• a computational tag in communication with the mobile electronic device;
• and
• a computer-readable storage medium in communication with the mobile electronic device, wherein the computer-readable storage medium comprises one or more programming instructions that, when executed, cause the mobile electronic device to:
• detect a computational tag within a near field communication range of the mobile electronic device,
• identify a document to be encrypted,
• transmit the document to the computational tag,
• receive, from the computational tag, an encrypted document, wherein the encrypted document comprises an encrypted version of the document that was to be encrypted, and
• store the encrypted document in a memory of the mobile electronic device.