Author Archives: Geoff

How do you charge an iWatch?

For almost two years I’ve carried a Fitbit Zip; Fitbit’s entry-level fitness tracker that runs on a watch battery and lasts a couple months. It has been great and I’ve rarely missed a day.

Recently, through a contest at work, I received a Fitbit Flex, an upgraded model that you wear on your wrist and charge every ~5 days (we’ll come back to that). After three instances where I failed to charge it and it stopped working, it now sits on my dresser, never to be worn again.

Like most nerds, I am excited to see what Apple releases on September 9th (even if it doesn’t ship until some time next year). I trust Apple will create a compelling product that solves a consumer need, makes use of innovative and difficult to replicate manufacturing techniques, and executes with a flawless user experience that will dovetail neatly into my life.

Critical to this execution will be power management; not just how long it lasts, but how you charge it.

Charging the Fitbit Flex required I create a habit with such an odd periodicity (not daily, not weekly) that it didn’t align to anything else I did in my life. Plugging in the devices required prying the tiny device from its rubber sleeve and plugging it into a single-purpose cord (compact for travel, impractical for a bedside table). Moreover, a key selling point of the Fitbit Flex is its sleep-tracking capability–so I can’t charge it at night.

Worse? Motorola’s beautiful new Moto 360 requires a charge twice a day.

So how do you charge an iWatch? I have two theories:

  • Unwittingly, continuously. Few companies could design a device whose daily motion would generate enough power to drive something more complicated than a watch (automatic or digital); Apple might be one.
  • Wirelessly, conveniently.  If the iWatch (/iWhatever) employs wireless charging, then an elegant solution is if the next iPhone could serve as its base station (while itself plugged in).

As I set my watch on my bedside table next to my charging phone, I could easily imagine placing it on top to receive a charge.

To take a step back: it would not be a stretch for the next iPhone to be able to receive its charge wirelessly through induction. Third party solutions exist but the technology would be far more compelling if the capability was built into the device. But if the iPhone could receive a charge I imagine the same antenna could be used to give a charge. When travelling, how great would it be to bring a single charger that accommodates both devices?

Background on Amazon phone’s rumored glasses-free technology

Boy Genius Report (BGR) just broke the first concrete news of Amazon’s rumored phone (including photos). One of the most compelling features is a glasses-free 3d display. The approach relies on eye-tracking (via a series of infrared cameras) for perspective shifting the display:

The device’s extra cameras are used to track the position of the user’s face and eyes in relation to the phone’s display. This allows Amazon’s software to make constant adjustments to the positioning of on-screen elements, altering the perspective of visuals on the screen.

The result is a 3D experience without the need for 3D glasses or a parallax barrier in front the LCD panel like the solutions used by the Nintendo 3DS portable video game console and HTC’s EVO 3D smartphone from 2011.

While this may sound sci-fi, Wiimote hacking hero (turned microsoft employee) Johnny Chung Lee first demonstrated a similar capability in a 2007 blog post and video:

From the blog post:

Using the infrared camera in the Wii remote and a head mounted sensor bar (two IR LEDs), you can accurately track the location of your head and render view dependent images on the screen. This effectively transforms your display into a portal to a virtual environment. The display properly reacts to head and body movement as if it were a real window creating a realistic illusion of depth and space.

With advances in miniaturization, and the use of on-board IR LEDs to illuminate irises, Amazon’s implementation appears to be a pretty straightforward use of technology demonstrated more than half a decade ago.

Heartbleed explained (two takes)

I appreciated the following succinct description of the Heartbleed vulnerability (from The Internet’s Telltale Heart):

Heartbleed is a bug in OpenSSL’s implementation of a small part of the T.L.S. protocol, called the heartbeat extension. A “heartbeat,” in this context, is like the “beep… beep…” of a hospital heart monitor: a quick way to check that the other end of a secure connection is still there. One side sends the other side a small piece of data, up to sixty-five kilobytes long, along with a number indicating the size of the data that has been sent. The other side is supposed to send back the exact same piece of data to confirm that the connection is still active. Unfortunately, in OpenSSL the replying side looks at the stated size of the data rather than at the actual size, and it always sends back the amount of data that the request asked for, no matter how much was sent. This means that if the stated amount of data is less than the amount actually provided, the response contains the data that was sent plus however much additional data, drawn from the contents of the computer’s system memory, is required to match the amount requested.

Of course, XKCD nails it in a more visual/narrative fashion.

Announcing: Kiddo–tailored selections for baby stuff


I’ve been working on a simple little web app to help new parents make smart product decisions.

Kiddo helps you find stuff that fits your baby. Diapers, toys, feeding supplies and more — all based on their height, weight, and birthday.

I’m really looking forward to getting this into users’ hands and getting to work on improving it based on real user feedback.

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