Apple Pencil: More Than a Stylus?

September 13, 2015 by Jennifer A. Diffley

The Apple Pencil was released this week with mixed reviews. Here's our look at the technology inside it and where Apple missed the mark.

Apple introduced its new Pencil to mixed reviews. Here's a look inside.

When the Apple Pencil was revealed at Apple's annual bacchanal, the reaction wasn't quite the widespread adoration to which the company has become accustomed: in fact, much of the audience laughed. Here's a look at the technology inside the pencil and how makers can use its shortcomings to build something even better.


First, a practical note: the Apple Pencil only works with the new Ipad Pro, the $799 version of the iPad that Apple hopes will compete with the Surface. Even though the new iPhones have 3D touch technology, the phones can't scan the signal emitted by the Pencil. So unless you have $1k waiting to throw at some new products, the $99 Pencil isn't for you. That said, the Pencil does have some interesting technology that could be taken and improved upon (and used with every device, not just the newest ones).

Signature- Palm rejection technology has been around for some time: it's the way previous devices have differentiated styluses from a hand placed on a screen. However, the pencil has a "signature," which means both hands and the pencil can be detected simultaneously. According to Apple, "When iPad Pro senses Apple Pencil, the subsystem scans its signal at an astounding 240 times per second, giving it twice the data points it normally collects with your finger." The signature, then, is essentially complexity. The iPad Pro knows it's not your hand because your hand isn't emitting a signal. The scanning also reduces latency, making the line drawn by the Pencil emitted almost as instantly as the graphite from a normal pencil. 

Pressure sensors- The pencil isn't capacitive, which means it doesn't operate the same way a finger does against a touch screen. Instead, the pen emits a signal that's scanned by the iPad to detect force, tilt, and pressure. The pressure sensors measure the force of the tip against the glass (hence the reason there's a small gap between the tip of the Pencil and the rest of the accessory: the harder the force, the more the gap is closed and the sensors respond in turn). The sensors are sensitive enough to select a single pixel, which is definitely better than any other stylus on the market.

Tilt sensors- Similar to the sensors that detect screen rotation in iPhones, the sensors detect movement variables that augment the width of the line on the screen. Tilting the pencil signals whether the line should be wider or thinner.

Bluetooth- Apple's standard connection. No surprise there, but it does mean the potential for the typical connection problems.

Lightning connector- The Pencil relies on the iPad's power to recharge its battery. Awkward, considering it essentially has a massive iPad sticking out of the place where the eraser would be.

So what can be improved upon?

Firstly, it's plastic. If Apple truly wanted its newest accessory to be more a tool and less a stylus, then it needs to feel like a tool. Handfeel is incredibly important to Apple, and the plastic doesn't signal high-end to the customer. Furthermore, high-end writing instruments simply don't have plastic bodies

And then there's the fact that the Pencil is only compatible with one product. It relies on the iPad Pro to do the bulk of the heavy lifting. A better stylus would include enough sophisticated technology to make it compatible with a range of devices.

It's also round, which means that clattering you hear is the sound of your $100 stylus rolling across the Starbucks floor under someone's foot. At least put a pocket clip on the end of it to combat physics.

And why isn't there a digital eraser like the 53 pencil has? The other practicality is storage. Some interesting stylus concepts on Kickstarter have addressed that issue, including one that uses the stylus as a wearable, but it's genuinely surprising that Apple didn't incorporate the Pencil's storage into the design of either the smart keyboard or the iPad Pro itself.

While we have to suspend criticisms until the Pencil is available for sale, it's safe to say the accessory is slick, but leaves much to be desired.