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Comment by doomlaser | Hacker News Reader

For comparison, here's another set of benchmarks from a guy who appears to use the same methodology (240fps camera, count frames between input and screen response in custom lightweight apps).

http://www.collectingsmiles.com/news/measuring-latency-in-co...

iPhone 5: 81 ms

Galaxy S3: 104 ms

Galaxy Note: 71 ms

Nintendo 3DS: 23 ms

PS Vita: 49 ms

And, to add a tv game console into the mix, apparently the latency between input on a PS3 wireless controller and home screen interaction is also about 50 ms.

http://www.gamasutra.com/view/feature/3725/measuring_respons...

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From the linked page: "THIS IS HOW COLORS! PERFORMS ACROSS DEVICES – WHICH MIGHT NOT BE HOW OTHER GAMES/APPS BEHAVE ON THOSE SAME DEVICES. Each device has their own way of doing input and rendering, and we have done more work on latency on some devices than on others."

In other words, one test was designed to be a benchmark from the ground up, and the other is a cross platform app.

So basically, for all we know the Android version of their app is just coded worse than the iOS one.

> and we have done more work on latency on some devices than on others.

Or, conversely, they had to work harder on their Android app to bring latency down to that of the iOS app. Just not enough information given to know.

It wouldn't make headlines because its not a sensational news.

Apple iPhone 5 touchscreen is as fast as Android. Meh.

The note has different tech in it than the vast majority of android devices (stylus support). Also, i could not find the result to verify whether it was for touch or stylus.

I came to the same conclusion (~85ms for the iPhone4s) in my own benchmark about a year ago, using Mobile Safari:

http://phoboslab.org/log/2012/06/measuring-input-lag-in-brow...

Not surprised at Nintendo's good showing. I remember noting that the older DSi felt incredibly responsive when using its stylus to draw. The several drawing apps I've tried on iOS haven't the same impression that your input is immediately laying down ink.

Now I want to know delay of trackpad on a Macbook Pro.

I've got no direct knowledge of this in particular but I've heard that the mouse movement is one of the highest level interrupts in the OS and won't be preempted -- so the number is probably very small but the response by the application when you click may be longer. Also, this is why sometimes you'll see the entire computer locked up except for the mouse movement.

Part of that is due to having a hardware mouse cursor. Basically all the interrupt handler has to do is load the new coordinates into some registers on the video co-processor and co-processor takes care of all of the work of blitting the mouse around the screen. It makes processing the mouse interrupts very light-weight.

Which OS and hardware platform are you referring to now?

I think this applies to most desktop OSes and nearly all the hardware platforms they run on, aside from virtualised ones.

Its interesting that the Wii U touchscreen has 53ms latency while the 3DS only has 23ms.

At a guess, the Wii U touchscreen is bigger so the scanning frequency would drop if they are both using the same tech.

Resistive screens don't need to be scanned like capacitive ones. The moment you make contact on a resistive film the controller can detect the resistance change and perform the A-D conversion. There's more latency in the host communication traffic than the conversion.

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