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- Interface extensively uses visual clues that make interaction extremely intuitive for elderly people who are often not accustomed to the use of conventional desktops. Visual clues take advantage of conventional metaphors and colour.
- The use of metaphors and colour scheme are both internally and externally consistent.
- Furthermore, speech based interaction reduces cognitive load by sequentially offering relevant options.
- The interface implements animated icons that symbolise receiving speech or avatar's speech, giving a clear visual representation of system's state.
- The problem with learnability might occur if the system fail to recognise the speech command because it can be extremely difficult to explain to the user what is wrong in the way they say things: users might be pronouncing words not sufficiently clear, there may be background noise, users can use out of vocabulary words.
Efficiency
- Speech based interaction alone may be inefficient for users who use the system very often. The fact that the system asks the same questions can become irritating after some point.
- Nevertheless, the targeted user group is elderly people for whom physical manipulation often may pose additional challenges. From this point of view the interface is considered efficient.
- The interface combines speech and touch which allows to delegate problems that would be difficult to solve with speech to a touch based interaction. For instance, In order to get additional information about an object the user needs to tap over the object. Another example is that the system records a history of spatial descriptions that the user can scroll through because memorising all the location is not feasible.
Safety
- The weakness of the system is that there is infinite number of speech commands that users can try.
- The interface improves safe by making the system ask interface is extremely safe because the system asks questions sequentially and in case of noisy input asks ask additional questions that help to disambiguate input.