I don’t think a user can handle a speech app with 25 commands.
It’s too complicated.Perhaps it is better to have very simple, very specific apps, that do specific things.
For example, the grocery list app, rather than an all purpose list management app.
How many different commands are there for a grocery app?- Mark an item- Clear an itemThat’s it, optionally add/remove items but they can do that manually.
That’s about 4. But a general purpose list app has 25, copying, moving, navigating, etc.
It all adds up[How simple can we make it?
Let’s venture into another example, if we are implementing a calculator all by voice. How many functions should it have before the human need an instruction manual?add/subtract/divide/multiply?
That’s only 4.What if we add a memory function and a square root, and even a power function?
It’s starting to sound complex. With a visual array of keys, it’s easy to know what you can push. With no visual, you don’t know what you can push.
What’s more you have to remember the magical phrase that you need to say to push it.
You have to remember it all. Better to have a whole suite of calculators, one for 4 functions just discussed.
One for calculating interest payments.
One for counting up a series of numbers.
One for binary math, etc.. (wait, who does binary math, no need for that one 🙂 )
What I am getting at here is that, I believe that we have to take seriously how much a person’s brain can handle when using a speech interface.
Either we make them really simple, or we need to implement a full fledged dialog system that can handle our babbling speech.