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3. Our controls interface is very similar to the iPod controls, which improved learnability. Unfortunately, some users were confused at first by the slider; some thought it was for volume instead of a time-controller. Once they tried it once, they realized what it was and thought that the scrubbing was very intuitive and natural.
4. As the race plays back, each piece of data is added exactly as it would be if you were recording the race again (the map updates, new strokes are logged, etc). This allowed users to playback a race and view the race again as an observer instead of a participant.
Playback Screen with navigation controls minimized
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