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This design emphasizes simplicity of the feedback collection process from a broad audience (i.e. public reception).
Analysis
Jenny uploads her image and adds commenters. She can create/edit groups by dragging and dropping users around.
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Jenny sees the comments as they come in. She can hover over users/groups to see their specific comments and annotations.
Analysis
Learnability
This UI could have some learnability issues, since there is very little textual guidance for both the artist and the commenters. The user will have to try dragging and dropping things around to figure out how to create/edit groups. However, this UI has a limited feature set, so it shouldn't take too long for the user to become familiar with what he/she can do. Furthermore, the commenter's UI at least mimics the real-life metaphor of an art gallery, so it should be relatively learnable.
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