All of these transitions were physical, but not all felt good enough
to foster repeated, non-functional fiddling. Perhaps most
successful by this metric were the slider phones, such as the
Motorola RIZR Z3. In this form factor, the numeric keypad was
hidden underneath the slider mechanism, with a 5-way
directional pad available in a closed state. This allowed many
actions to be performed without actually sliding open the phone.
In practice though, it wasn’t functional necessity that caused
people to slide the phone open and closed repeatedly
throughout the day. They did it because it felt and sounded good.
Why does this mechanism feel good enough to invite repeated
non-functional triggering? For one, the sliding movement is
dampened, with a spring providing slight resistance until it
reaches a catch point where the force is reversed and the cover
is accelerated to its final open state. This avoids accidental
opening, but also results in a satisfying “pop” sound as the
mechanism takes over and amplifies your action. Sliding is also
easy to perform discreetly with one hand, without requiring wrist
or arm movements.
Figure 2.x iOS list view scrolled upwards beyond its final list item
Purely digital products can also exhibit moments that cause
delight in repetition. One example is the “bounce” animation at
the bottom of a scroll view in Apple’s iOS. As the user swipes
their finger upward the list scrolls up and off the screen, but
when the user reaches the bottom it doesn’t just stop abruptly.
There is a subtle animation, where the whole list pulls up slightly
farther than the last item, before easing back to let the final entry
sit at the bottom of the screen.
The functional reason for the scroll view bounce is to act as
feedback that the user has reached the bottom of the list.
However, even though the animation is purely visual, it “feels”
good enough that one can find themselves scrolling again and