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This is the voting interface used by partygoers. A key design choice was to use plus and minus buttons to vote for songs. Originally, we had considered using a sliding interface. However, we noticed during paper prototyping that many people pressed the arrows that were supposed to afford sliding instead of actually sliding. The use of buttons ended up being natural and easy to implement. Only the song title and artist are displayed versus more possible meta data associated with a song such as length. Only those two fields were used to keep the interface simple and draw attention to the most important information about a song.
The icons on the buttons changed as a result of computer prototyping.
This was the original interface.
This is the new interface.
Computer prototyping showed that plus and minus buttons were more compact than words on a mobile phone device enabling the buttons to stay on the same line. In addition, neutral was changed to a vote count to give information to the users about how popular a song was. A vote count also makes it clear whether or not the users vote had been counted, a problem noticed from the computer prototyping.
Implementation
Describe the internals of your implementation, but keep the discussion on a high level. Discuss important design decisions you made in the implementation. Also discuss how implementation problems may have affected the usability of your interface.
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