Fitts law vs. Tactile law

Fitts law was created in a different world, a time of mouse not thumb. This doesn’t mean that the concepts are not useful.

Instead of measuring from the current cursor position to the next position we are dealing with the origin that depends on where the hands are held, and maybe where the outstretched digit is reaching.

What about the modern UX trend wrt touch devices. The fact that we can now interact with objects themselves vs. other representations.

– Instead of touching a button to bump up the volume, move the volume dial

– Instead of selecting a radio button and tapping the “save”, just select the item

– Instead of having an image of the map, have it be an embedded map entity that you can interact with.

The list goes on and on. People enjoy bringing skeuomorphism into the mix too.

My favorite app experiences know how to balance Fitts law and the world of tactile. One example is an eBook reader. It is natural to try to mimic books, and that is how you get actions such as turning the page. Very discoverable and it fits in nicely.

However, swiping to get from page to page is not how I like to move around in a book. I much prefer using my right thumb to quickly tap to move to the next page. Maybe not as discoverable, but a much simpler gesture… you don’t have to take your hand off to make the gesture and then putting it back again. Changing pages is something you do constantly, so optimizing that action is important.

Thus, a nice marriage of different ways to do the same thing.