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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 visibility problem noticed from the computer prototyping. Overall, the design of the voting interface was driven by simplicity and this fact was positively commented on in the heuristic evaluations.
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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With regards to evaluating the results of testing and prototyping, it was very useful to aggregate all the comments. This made it easier to determine the importance of various comments since recurring problems indicated that the issue was a valid complaint. We attempted to figure out which features to prototype but trying to put ourselves in the user's shoes and thinking about the most critical functions.