Softkeys, lock/power, volume, etc. Mostly that they need to press in or be clearly of a different shape to afford, must light up like keypads, must be labeled unambiguously and the label must light up, must be near labels which means SKs need to not be 5 feet from the screen, etc.
Problem
Solution
Outside of Keyboards & Keypads] and Directional Entry controls, practically all mobile devices have numerous additional keys. Regardless of their function, all must comply with some basic behavioral standards in order to be useful, usable and valuable to the user.
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must have effect immediately, regardless of the type of effect. must have an on-screen effect; even if the primary effect is something else, like a volume control, the change must be indicated and the new setting displayed briefly. Can be in annunciator, via a pressing keys with backlight on generally should change the key backlight haptic or audio response also... nice to have them "click" or otherwise use response to indicate the key has been activated...
unambiguously label on key... must be visible in all conditions labels and descriptions for on-screen effects, notifiers, etc. must comply with the hardware label. Make on-screen stuff about it adjacent to the key whenever possible; can even point to it for help or tutorials...
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