Of Touchscreens, Styluses, Elegance, and Kludge

The original Apple iPhone

Elegance: N. The quality of innovative simplicity. In engineering, an elegant design is one that solves a complex problem with breathtaking simplicity, provoking all the engineers who observe it to raw envy of the designer’s mad skillz.

Kludge: (pronounced klooj) N. An awkward, over-complex, but nonetheless minimally functional design. In engineering, a kludgey design is one which provokes its designer to say, “There’s got to be a better way to do this…”

When I first saw an Apple iPhone, the elegance of the capacitative touchscreen blew me away. With a single electronic input device, Apple’s engineers had reduced the number of mechanical switches in a smartphone from roughly 65 to a measly 5, compared to a Blackberry. It vastly reduced the chance of mechanical failure.

The capacitative screen was an improvement on the Palm pressure-activated screen as well, requiring neither pressure nor a stylus. The old Palm screens would wear out, since they depended on making physical contact between the layers of the screen. This could never be a problem with the Apple screen.

But this simplicity and improved reliability had a cost — precision. The touchscreen needed a touch 6 mm (1/4 inch) in diameter — the size of a small finger — in order for the contact to register. This was simultaneously both too big (for drawing or handwriting) and too small (for users with larger hands.)

The first touchscreen styluses were invented as a solution to the “too small” problem. With a conductive body and a rubber tip just big enough to trigger the screen, they enabled people with big hands to use the onscreen keyboard and small controls. For the iPhone, this was (almost) enough.

With the iPad, Apple introduced a screen big enough for handwriting recognition and drawing to be irresistible to app developers, but the precision problem remained. Now third-party hardware companies started getting into the act with “precision” styluses. The problem with these styluses?

Every single one of them is a kludge.

Even the passive precision styluses are kludgey, though they are better than the electronic or bluetooth styluses just because they’re simpler. They have a either a transparent or an open 6 mm tip so that the user can see the line she’s drawing. But the tiny connection of the 6 mm tip to the stylus body is delicate and prone to failure. The flat transparent tips can trap grit that will scratch the screen, no matter how carefully you clean before using.

The electronic styluses generate an electronic signal that fools the touchscreen into thinking that the tip is bigger than it really is. These can have parallax problems, meaning that it’s hard to keep the signal centered on the tiny tip when the user holds the stylus at an angle, producing position error. They are also useless if their batteries run down.

Most of the Bluetooth (BT) styluses are trying to reproduce the experience of drawing on a PC or Mac with a graphics tablet. They generally incorporate a precision tip, either passive or electronic. They also send extra information such as angle, tip pressure, and position via BT to the iOS device, that can be used to implement pressure sensitive response, angle response, and palm rejection. But BT can be slow, and the low energy version used in these styluses can disconnect easily. They don’t connect to the iPad or iPhone as a whole, but only to individual apps that support their special features.

Look at the Amazon ratings for these things. The very best average rating, for durable precision or BT styluses with decent manufacturing quality, is four stars. That’s because people don’t read carefully, run afoul of an admitted limitation, and give a bad rating.

I love my new Pencil by FiftyThree. But I would never recommend it to anyone who didn’t use or want to use at least one of the apps on its partners list, and who understood that not all of the features are supported by every app on the list.

Only the Apple Pencil isn’t a kludge. But it isn’t elegant, either — not to an engineer. Not by the definition above. It works because the screen on the iPad Pro is no longer a pure capacitative touchscreen. It has been redesigned to incorporate other means of getting the position, angle, and pressure information that an Apple Pencil provides, as well as capacitative touch. Without that hardware support in the screen it would be just another BT stylus — which is exactly why Apple never released a stylus until it had the more complex screen in place. It’s that hidden hardware support that keeps the design from seeming elegant, to me. Rather, it’s an example of creeping complexity — not necessarily a bad thing, but not elegant. The truly elegant solution lies elsewhere — and no, I don’t know what it will be.

But when I see it, my jaw will drop.