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Learnability: The notes management portion of our interface in this design shares some external consistency with interfaces such as the Mac OS X finder, but learnability is hampered by the fact that it does not allow you as much freedom as a normal file system hierarchy; it might take a while for a user to realize that they must create a class before they can create notes for that class. The text editing portion of our interface maintains external consistency with many other text editors, and as such is very learnable. The fact that we limit the amount types of formatting you users can do to things that are useful for notetaking (for instance no font selections, no text color) also makes the interface simple simpler and easier to learn. The most novel part of our interface is the integration with a smartphone. The initial QR code app download might be confusing, but we hope that most smartphone owners will be familiar with using QR codes to download apps. Usability testing might be required to see if that is true. We hope that we can get response times fast enough between saving an image you've a user has taken and it appearing in your their camera roll that users will not be confused about where their picture has gone, otherwise that might also be a learnability barrier.
Efficiency: Creation of new notes is not very efficient in this design, since on first launch the user must create a class to categorize the notes in first. Even after that, users can't just create notes and decide where to save them later, like they might if they were saving a file on their computer. Instead, they have to decide where the notes are categorized first. However, the efficiency sacrificed in the creation of notes is gained when reviewing the notes, since imposing an organizational system saves users the trouble of inventing one later. Furthermore, the paned display that allows you to view the entire hierarchy at once makes it easier to see where you might have put notes that you want to review. The search bar also allows for efficient locating of notes.
Safety:
Design 2
In this design, notes are stored in a hierarchy that mimics a traditional directory hierarchy.
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