Numeric keypads - which mental model to use?
Screen at an M&S till when inputting a quantity for a loose item
Calculator screen from my iphone
Decimal keypad to input numbers into a field on an iphone.
Old school. Card reader for home use and a good old fashioned calculator…
Keypad for card reader at M&S
Keypad for the phone - on my iphone
An old fashioned push button telephone…
Numeric keys on a keyboard.
Telephone keypads, calculator keypads, and inputting text in a form. What are the appropriate mental models to use for each ocassion.
So this is interesting. Today I was in M&S paying for a loose item (yes, OK, it was a sticky bun, not a healthy piece of fruit) using the self service till.
I went to input ‘1’ on the touch screen keypad shown on the far left – doing so quite quickly. But I aimed top left and input ‘7’. A slip. But why did I do that? Am I the only one that has?
I then looked at the keypad for the card reader and the numbers are formatted the the other way round.
What about my phone I thought…
The calculator screen is the same round way round as the screen on the self service till.
The numbers for dialling a phone number are the other way up.
But the decimal key pad that is presented when you input numbers into a field in a form are the same way round as a phone or when you put in a PIN.
Maybe my subconscious mental model was form filling, not numbers???
Oh it would be SO interesting to test this - what is the common mental model for a touch screen till where you are inputting quantity.
I guess these affordances provided by designers and manufacturers now, must be based on something inherited from items designed decades ago.
Does the use of a touch screen complicate matters in this instance when assessing our mental models? Do we subconsciously think ‘form on a computer’ and not ‘till’ or ‘calculator’?
Does it just depend on what you were doing most before you went to use the till (context) - dialling lots of phone numbers (do people do that much now?), getting cash out the cash machine, or more immediately what did you do on the previous screens - I need to go back to buy more sticky buns and pay more attention to the previous screens!
As I said it would be so interesting to test this out.
Do the mental models vary around the globe…
Interesting article on TNW News that discusses the history of these keyboards.