While the Apple Pencil is designed as a sketching tool for creative professionals, MacRumors reader Simon Gladman has created three Swift demo apps that show the accessory being used for three unconventional purposes -- as a weight scale, controlled synthesizer and 3D controller for image editing.

PencilScale


PencilScale, based on Goodman's Plum-O-Meter, is an experimental app that uses a homemade harness to turn the Apple Pencil into an electronic scale that is highly sensitive, but not incredibly accurate.

The experiment works by subtracting the touch's force from a base weight, which is "set as the current touch force when the 'zero' button is pressed," and multiplying it by 140 for a very rough weight in grams.

PencilSynth


PencilSynth is an AudioKit-powered synthesizer that can be controlled by the Apple Pencil depending on its orientation and position.

  • Apple Pencil's horizontal position on the screen controls frequency

  • Apple Pencil's vertical position on the screen controls the modulating multiplier

  • Apple Pencil's altitude angle controls the carrier multiplier

  • Apple Pencil's azimuth angle controls the modulation index

PencilController


PencilController is an experimental image processing app that uses the Apple Pencil as a controller for the fine setting of parameters on Core Image filters.

The demo has three image filtering modes:

  • Hue/Saturation - Apple Pencil's azimuth angle controls hue and its altitude angle controls the saturation

  • Brightness/Contrast - Apple Pencil's altitude angle along North/South controls contrast and the angle along West/East controls brightness

  • Gamma/Exposure - Apple Pencil's altitude angle along North/South controls exposure and the angle along West/East controls gamma

Gladman explains that "the app uses a spring loaded pattern, so the user needs to hold down one of the mode keys in the bottom left of the screen to stay in the filtering mode."

The source code for all three projects is available on GitHub.

Related Roundup: iPad Pro
Related Forums: iPad, iPad Accessories

Top Rated Comments

FlexMonkey Avatar
96 months ago
I know this is sounds cool. But come on guys I'm tired of hearing this non-sense use of technology. There is abviously a much better device for such thing and it doesn't cost a lot of money to have one. I'm talking about the scale and somebody did it on iPhone 6S 3D Touch too. It's because you can it doesn't mean you have too.
Hi!

I'm actually the same guy that did the "Plum-O-Meter" for weighing things on an iPhone :)

Of course there are better devices, but I'm interested in experimenting, tinkering and playing then seeing what results. Actually, using the Pencil as a controller works really well for the fine adjustments in the image processing app and the fact the it has five degrees of freedom makes it a unique input device for the audio app.

Without some left field thinking, we'd all be using abacuses!

Cheers!

Simon
Score: 16 Votes (Like | Disagree)
Waxhead138 Avatar
96 months ago
Aren't the phrases "Highly Sensitive" and "Not Incredibly Accurate" a bad combination under pretty much any circumstance?

.....As a side note, those two phrases remind me of almost every girlfriend I've ever had, the first phrase typically causing the second.... ;)
Score: 7 Votes (Like | Disagree)
teslo Avatar
96 months ago
I know this is sounds cool. But come on guys I'm tired of hearing this non-sense use of technology. There is abviously a much better device for such thing and it doesn't cost a lot of money to have one. I'm talking about the scale and somebody did it on iPhone 6S 3D Touch too. It's because you can it doesn't mean you have too.
yeah, why would anyone ever want to do things?

i, for one, am witnessing exactly what i'd hope would start happening upon the release of a new device: tinkering, feedback, and constructive criticism. i'm sorry you're tired, i hear energy drinks are all the rage nowadays.
Score: 6 Votes (Like | Disagree)
Makosuke Avatar
96 months ago
Aren't the phrases "Highly Sensitive" and "Not Incredibly Accurate" a bad combination under pretty much any circumstance?
Nope, from a scientific terminology perspective, that actually makes perfect sense.

Accuracy, scientifically speaking, is how close to the real value a measurement will produce.

Precision (aka sensitivity) is how small of a quantity you can measure, accurately or otherwise.

And repeatability is how close to the same value taking the same measurement at two different times will produce, accurately, precisely, or otherwise.

So: An accurate scale will tell you something weighs 502 grams when it weighs 502 grams. A precise scale will tell you that something weighs 498.93 grams, although it might actually weigh 502.00 grams if the scale is not also accurate. And a repeatable (and precise) scale will tell you that something weighs 498.93 grams every time you weigh it, although if it's not also accurate it might really weigh 502 grams.

This particular "scale", silly or otherwise, will give you a lot of digits of precision on the weight measurement, so it's quite precise. It however isn't calibrated at all, so the accuracy is bad. No idea whether it's repeatable or not.
Score: 5 Votes (Like | Disagree)
nagromme Avatar
96 months ago
Think what you could do with 3 pencils! You could control that synthesizer with one, and jam the other 2 in your ears until the racket stops.
Score: 4 Votes (Like | Disagree)
joueboy Avatar
96 months ago
I know this is sounds cool. But come on guys I'm tired of hearing this non-sense use of technology. There is abviously a much better device for such thing and it doesn't cost a lot of money to have one. I'm talking about the scale and somebody did it on iPhone 6S 3D Touch too. It's because you can it doesn't mean you have too.
Score: 3 Votes (Like | Disagree)

Popular Stories

maxresdefault

Apple Announces WWDC 2023 Event Taking Place June 5 to 9

Wednesday March 29, 2023 9:58 am PDT by
Apple today announced that its 34th annual Worldwide Developers Conference will take place from Monday, June 5 to Friday, June 9. Like WWDC 2020, 2021, and 2022, WWDC 2023 will be an online event for the most part, and it will be open to all developers at no cost. Subscribe to the MacRumors YouTube channel for more videos. Apple will provide online sessions and labs, which will allow...
iPhone 15 Pro Buttons CAD Leak

iPhone 15 Pro Low-Energy Chip to Allow Solid-State Buttons to Work When Device is Off or Out of Battery

Wednesday March 29, 2023 1:54 am PDT by
The iPhone 15 Pro and Pro Max will use a new ultra-low energy microprocessor allowing certain features like the new capacitive solid-state buttons to remain functional even when the handset is powered off or the battery has run out, according to a source that shared details on the MacRumors forums. CAD-based render of new solid-state buttons on iPhone 15 Pro models The source of this rumor is ...
CarPlay Phone Call

General Motors to Phase Out Apple CarPlay Starting This Year in EV Transition

Friday March 31, 2023 8:43 am PDT by
General Motors (GM) will phase out Apple CarPlay and Android Auto in its vehicles starting this year, shifting to a built-in infotainment system co-developed with Google (via Reuters). GM owns Buick, Cadillac, Chevrolet, and GMC in the United States. It will stop offering Apple CarPlay and Android Auto starting with the 2024 Chevrolet Blazer, which goes on sale this summer. The company plans ...
iPhone 15 Pro Multi Purpose button Mute Switch Feature Green 2

iPhone 15 Pro Rumored to Feature Multi-Use Action Button Instead of Mute Switch

Wednesday March 29, 2023 7:28 am PDT by
iPhone 15 Pro and iPhone 15 Pro Max models are rumored to feature a customizable Action button like the Apple Watch Ultra, according to a MacRumors forum member who leaked accurate details about the Dynamic Island on iPhone 14 Pro models last year. The source claimed the Action button will replace the Ring/Silent switch that has been included on every iPhone model since 2007. They did not...
iOS 16

iOS 16.4 Now Available for Your iPhone With These 8 New Features

Friday March 31, 2023 8:55 am PDT by
Following six weeks of beta testing, iOS 16.4 was released to the public this week. The software update includes a handful of new features and changes for the iPhone 8 and newer. To install an iOS update, open the Settings app on the iPhone, tap General → Software Update, and follow the on-screen instructions. Below, we have recapped eight new features and changes added with iOS 16.4,...
iOS 17 on Phone Feature

Three New iOS Features Coming to Your iPhone Following Apple Music Classical

Thursday March 30, 2023 7:13 am PDT by
With the Apple Music Classical app and an Apple Pay Later early access program now available, the list of previously-announced iOS features that have yet to launch is beginning to shrink. However, there are still a few features we are waiting for. Below, we have recapped three more iOS features that are expected to launch in 2023, including an Apple Card savings account for Daily Cash,...
apple mixed reality headset concept by david lewis and marcus kane

Kuo: Apple Mixed-Reality Headset May Not Appear at WWDC as Mass Production Pushed Back Yet Again

Thursday March 30, 2023 4:50 am PDT by
Apple has again pushed back mass production of its mixed-reality headset and the device may not appear at this year's Worldwide Developers Conference (WWDC), Apple analyst Ming-Chi Kuo today said. Apple headset concept by David Lewis and Marcus Kane In a tweet, Kuo explained that Apple "isn't very optimistic" about whether the headset will be able to create an "iPhone moment." As a result,...