A method of encrypting information using a computational tag may include, by a mobile electronic device, detecting a computational tag within a near field communication range of the mobile electronic device, identifying a document to be encrypted by the mobile electronic device, transmitting the document to the computational tag by the mobile electronic device, receiving, from the computational tag, an encrypted document, wherein the encrypted document comprises an encrypted version of the document that was to be encrypted, and storing the encrypted document in a memory of the mobile electronic device.