Human–Computer Interaction

79

HCI desIGn

initial choice will purposely not be well thought out, just to illustrate

that a naïve and hurried choice would expose the application to be at

high risk of eventually failing in terms of usability and user experi-

ence, even if it computationally satisfies the required functionalities.

• Select song

• Select temp

• Play (Show chords)

• Show instruction

• Scroll and select by touch

•

Finish by selection, OK, return button

from a main menu/

screen touch

Figure 4.23 A typical usage scene 2: Interface looks for three subtasks (e.g., song selection,

tempo selection, and showing instruction).

Initial Play View

Hey Jude in C

C

- -

4

G

Information

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