[arendtio]

Reminds me of the time I built a BabyButton, which was built in a way so that a baby could use it. Instead of the normal click behaviour, it was using the touchdown event, because that way the kid saw that something happened, and there was no problem with holding the button too long or moving the finger while still holding the button.

Whether you should build systems for that age group is an entirely different topic, but I found it a good challenge to design something that fits the user's needs.

[slazaro]

It's interesting that we're so used to the GUI buttons having that specific behavior of only triggering when releasing, even if you exit and enter the button area while holding the mouse button down, etc.

IRL 99%+ of buttons work by just doing the thing as soon as you press them. But a button that works like that in a GUI would feel wrong.

[IdiotSavage]

> But a button that works like that in a GUI would feel wrong.

No, it doesn't. It feels way more responsive.

My pet peeve is "stopwatch apps" which trigger on release instead of on press. When timing something where fractions of a second matter, most people won't realize that it triggers on release and tap down when they want to start / stop, adding some arbitrary delay until they actually release the button.

[d12bb]

No, even for stopwatch, trigger on release is the correct choice, as it’s more precise.

When tapping, I have to see, or in case of watching for some event to happen to stop the time, feel/guess when exactly the distance between screen and finger approaches zero. With a stop button triggered by release however, I can just calmly rest my finger on it and raise when the event happens, without any guesswork.

[SoftTalker]

How does a real stopwatch work? Hint: it starts/stops on press, not release. So that's what the app should do, to map with prior expectations.

"Nobody uses real stopwatches anymore" might be somewhat true, but in athletics training they still do, and it just shows that it's not possible to adequately reproduce a thing on a touch screen and have it be as functional as the real item. A stopwatch app on a phone will always be a poor substitute for a real stopwatch.

[hananova]

Yes, but on a real stopwatch, or on a computer mouse, you can rest your finger on the button with almost but not quite enough force to actuate it, and activate it with a press.

On a touch screen you have to hover your finger over the button and move it down some indeterminate distance to actuate the button. The equivalent to the above example for a touch screen is to activate on release, as you can rest in a state “ready to click” just like on a physical button that way.

[IdiotSavage]

Interestingly the "activate on release" logic was implemented in computer GUIs long before touchscreens were common, used purely by mouse-click (a physical button).

[IdiotSavage]

My point was about user expectations / users not being aware when the button triggers. Your argument has nothing to do with that.