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Frodo first logs in to his account, where he can view his existing projects and create new projects. 
Frodo creates a new project to analyze Africa's WiFi coverage. The screen is initially a world map, with initially shows thumbnails of visualizations, from which Frodo selects a geographical map. In the left toolbar, there is an empty list of "Current Data Sets" in the left toolbar. Frodo clicks on the "+" button to import data into the projectmap. This brings up a box where he can search and browse data sets and drag them into his Current Data Sets list. 
After importing the data he needs, he can see the data sets visually laid out on the map. The map's zooming and panning functions are externally consistent with other maps, i.e. Google Maps. 
The Current Data Sets list allows him to toggle each set on/off in the map, and provides a legend of how the data is visualized. The timeline on the bottom shows a line graph of data that varies over time. The timeline has its own legend where data sets can be toggled on/off. Frodo can zoom in and out of the timeline (e.g. view by years, months, or days) with the slider at the top of the timeline. To display a time average of the data on the map, he can use his mouse to highlight a selection of the timeline.
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Frodo will want to add hypothetical new Boingo WiFi towers to the map to improve his score. On the lower left toolbar, he can add new towers to the Boingo WiFi towers data set. He can click and drag a new tower onto the map, and data related to the new tower will display right next to the mouse. The data on the right-hand side of the screen will also update automatically as Frodo moves his mouse around the map. 
To see data for towers on the map, Frodo can hover over them, and a box will automatically pop up next to the tower. To edit this data, Frodo must click on the tower, then the box of data will remain visible when the mouse is moved. He can adjust parameters with sliders, and see tradeoffs between different factors such as cost, power, coverage area, etc. There are also buttons to add a note and to delete the tower. To move the tower, Frodo can click and hold down the mouse for ~1 second, then drag the tower to a new location. 
If Frodo gets stuck, he can ask his friend Samwise for help. First, he might want to write some comments on the map itself. He can click on a commenting toolbar on the left side, which will have tools for adding textboxes, circling areas, etc. Although not pictured here, the toolbar will have external consistency with programs such as PowerPoint and Photoshop.
To share his project with Sam, Frodo clicks on the "Share" icon at the top of the screen. A window drops down from the Share icon, where Frodo can enter Sam's username/email, set editing privileges for him, and add a message. Sharing allows for real-time collaborative editing, as it does in Google Docs. 
After Sam tells Frodo that his analysis looks perfect and wonderful, Frodo is ready to "publish" a final report to his boss, Gandalf. Functionally, publishing sends only the a copy of the current project, and does not send real-time updates like sharing does. Ideally, Frodo would be able to select which parts of the project to include in the report, and provide extra commentary/analysis for his boss. However, since we are focusing on the UI for visualization, Publish will look essentially like Share, at least for now.
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