CellMailGraph is a graphical interface that uses the metaphor of a radar to screen our inbox. The application has three levels of interaction, that are discussed below.

Let's see what an inbox looks like on a Nokia 6630 phone first.

Dots: every dot represents an email. The last email that arrived to the inbox throbs allowing for easy spotting.

Colors: The colors identify tracked contacts. The messages coming from unmonitored email addresses are grey. As dots get further from the center and, therefore, older, they will become more and more transparent (future development).

Concentric Rings: The concentric rings comprise a time period of 24 hours. The emails older than that stack in the corners of the image.

Size: The dots are proportional to the size of the email.

Darker blue circle: It refers to the total amount of unread emails in the mailbox. With the current settings, a circle as big as the screen refers to over 100 mails.

Text: the keywords found in any of the messages are written down on the screen in the color that matches the sender, tracked or not tracked.

Target pointer: acts as a mouse that allows us to navigate the graphical inbox and select dots/emails in a gaming fashion using the arrow keys. Press # once the pointer is on a dot to show the actual message.

Cognitive factors

The application offers three 3 levels of interaction:

1. On the first level, keeping in mind that the goal of CellMailGraph is to provide in a glance an idea of the new emails that we got, to come up with a visualization I decided to use some the features that are caught by our preattentive vision system, which performs the first degree of perception, when we haven't paid attention to the object of observation yet:

• simple shapes
• color codes
• arrangement
• 2D graphics

2. On the second level, a more attentive observation of the graphic map of or inbox reveals other information:

• a throbbing dot guides our vision and informs us of which was the last email that we got
• the concentric rings set a frame of 24 hours. Every ring starting from the middle represents two hours from the current time on, so we can also have an idea of the passing of time and the amount of emails we received during a specific period of time.

3. On a third level of usage, CellMailGraph acts as a graphical interface to our mailbox. A target pointer allows us to spatially navigate our inbox and select the dot or email that we want to check. Clicking on the dot displays the content of the message on the cellphone screen.