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by robertlagrant 3224 days ago
The only new thing was a capacitive touchscreen, which allowed more responsiveness to a touch input. It just came along at the right time.
2 comments

That wasn't even new, it's just that no other manufacturer dared to put out a phone at $600 (that's with contract, single carrier exclusive).
Capacitive screens were less responsive than resistive screens.

The difference was that you used your physical finger instead of a stylus. Personally speaking, I preferred resistive screens for their responsiveness and accuracy.

The capacitive screen was needed for "pinch to zoom" and other gestures of the modern era. The delay in the UI compared to resistive screens (as well as the higher-CPU time required for processing) turned out to be a smaller deal than multi-touch technology.

Is there some more information on that? I believed so far (or the industry made me believe) that capacitive screens were much faster than the resistive ones.
I don't have like, hard tested data. But the delay is enough that experience was all I needed to convince me.

Nintendo DS / 3DS and Wii U are all resistive screens. I also have experience with resistive screens of Palm Pilot and Palm phones of the early 2000s. And all of those were more "responsive" than a 2007-era iPhone, despite the iPhone's significantly higher processing power.

Play a serious game like Monster Hunter (very timing intensive) and compare it to a serious timing-intensive game on a capacitive screen (I know I've seen people play Marvel vs Capcom 2 on an iPhone emulator...). The lag and delay is noticeable even in the modern era.

But people wanted multi-touch pinch to zoom. Capacitive sensing also requires a microcontroller to literally "charge up" the screen over and over.

When your finger is on the screen, it "charges up slower" (because your finger changes the capacitance at that location). Innately, that "charge and discharge" cycle requires a measurement over time.

And to make sure that power isn't wasted, only one part of the screen is often tested (there are grids and stuff that then calculate where the fingers or multiple-fingers are located). So innately, there's a delay as the "scan-lines" of the sensors test each point of the screen.

Resistive screens instantly tell you where the stylus is without any such delay or processing. So it just makes sense.

I don't have any direct links, but the latency on processing touch input from a capacitive display can be as high as 40ms, remember there is a lot of filtering going on and spurious crap that has to be filtered out.

Think how crazy the trackpad goes on a cheap laptop when you plug in a knock-off power supply with poor power conditioning.