Efficient attachment of files from mobile devices

A computing device configured to for attaching a digital file from a mobile device to a draft email message on a client device interconnected to an email server by a computer network, the computing device comprising:

• a processor;
• and
• a memory operatively coupled to the processor, the memory containing instructions executable by the processor to cause the computing device to:
• receive, from the mobile device, the digital file along with an authentication token and an email identification of the draft email message;
• authenticate, using the received authentication token, with the email server for access to a server copy of the draft email message on the email server;
• and
• upon successful authentication, upload a copy of the received digital file to the email server as an attachment to the server copy of the draft email message on the email server, the server copy of the draft email message being identified by the received email identification, thereby attaching the digital file from the mobile device to the draft email message without a direct local connection between the mobile device and the client device.

A mobile device, comprising:

• a processor;
• a camera;
• and
• a memory operatively coupled to the processor, the memory containing instructions executable by the processor to cause the computing device to:
• capture, via the camera, an image of a machine-readable label shown on a display of a client device used to compose a draft email message;
• decode, with the processor, the captured image of the machine-readable label to derive a network address of a webpage, an authentication token, and an email identification identifying the draft email message being composed on the client device;
• load the webpage at the decoded network address in a web browser on the mobile device;
• and
• upon receiving, via the webpage in the web browser, an input to upload a digital file from the mobile device, transmit, from the mobile device, the digital file to an upload server along with the decoded authentication token and the email identification of the draft email message, the authentication token being useable by the upload server to authenticate with the email server and upon authentication, transmit the digital file to the email server as an attachment to a server copy of the draft email message on the email server identified by the email identification.