Hacking on the Pebble Smartstrap

Maker News Technology Wearables
Hacking on the Pebble Smartstrap
The Pebble Rocks Boulder Hack-a-thon (Credit: 23rd Studios)
The Pebble Rocks Boulder Hack-a-thon. (Credit: 23rd Studios)

With the arrival of the Pebble Time Round this week, the smart watch market is heating up. We’ve been talking about wearables technology for a long time, but designing one people would actually wear has been elusive. As almost 90% of the standard watch market is made up of round watches, the new Pebble has joined an exclusive club. It’s one of the few smart watches that comes in a form factor that people who aren’t geeks like us are willing to sport.

The new Pebble Round (Credit: Pebble)
The new Pebble Time Round. (Credit: Pebble)

But perhaps the most intriguing thing about Pebble’s new hardware platforms is the smart accessory port, which will let you build a smart strap for your smart watch.

Like the arrival of the smart phone before it, which turned out to be the driver behind the Internet of Things, the smart watch could turn out to be a powerful lever to drive adoption in wearables, and the smartstrap could prove to be a crucial factor in making that possible. The smartstrap is remarkably open, and offers the potential to integrate maker-made hardware directly into Pebble’s existing ecosystem. 

We got a taste of the Pebble’s smartstrap back in May at Maker Faire Bay Area, where we talked to Thomas Sarlandie — a developer evangelist at Pebble — about the new Pebble Time and the prototype of SeeedStudio’s smartstrap which was on display for the very first time in public.

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A couple of weeks ago Pebble ran their very first hack-a-thon to focus on the Pebble smartstrap. The event was held in Boulder, Colorado, and was — maybe predictably at that point — called Pebble Rocks Boulder.

We caught up with  from Diana Jannuzzi, from Viget, who ran the hack-a-thon in Boulder to talk about the event ant how it came together.

We invited 70+ iOS developers, networking engineers, electrical engineers, designers and makers to participate in the hackathon at Galvanize coworking space in Boulder. The event attracted many local tech professionals, but we also had participants travel from places like Portland, New York, and Texas. In addition to the young professionals you might expect at your typical hackathon, we were excited to welcome a mother-son team, as well as a team proudly known as Hack Dads.

Prior to the event, we encouraged registered participants to join a Slack channel Pebble created so they could share interests and form teams. We accepted about 10 individuals who applied solo or as a pair–the rest applied as a team. In the end, there were 23 teams, each creating a unique project.

The majority of teams came in fresh and began brainstorming once we revealed the treasure chest of components (everything from multiple iRobot Create 2’s, to GPS units from SeeedStudio, to a rubber duck).

A few teams came in with a rough idea in mind (“it would be fun to do something related to survival”), but had not through execution. Even fewer had a specific goal in mind. For example, team Engineerable knew they wanted to make an audible notification attachment for their kickstarter-funded Pebble Time charging dock, but they had no idea how they’d accomplish it. At the event, they decided to 3d-print a gramophone-inspired enclosure that worked as a mechanical amplifier.

We also asked Diana about the projects, and surprises, that came out of the hack-a-thon.

The first night, we overheard many teams talking about how they hoped to use accelerometer data, and we worried there would be a ton of overlap. However, that wasn’t the case at all. The variety of creative ways teams made use of the Pebble Time surprised us. For example, who knew you could hack a 3d printer to control it with a watch?

The amount of teams that took advantage of the 3d printers on site also surprised us, especially considering most teams did not have previous experience working with them. In the end, only a handful of teams did not use them. As sponsors, LulzBot not only provided printers, but also sent representatives who gave a presentation during the kickoff, which helped get ideas rolling. They stuck around the rest of the weekend to answer questions and give teams advice on how they could incorporate 3d-printed materials in their projects.

We were also impressed with the quality and level of completion of the projects. It was exciting to see so many working prototypes at the demo night Sunday. 

All of the projects from the hack-a-thon can be found on the event’s project page, but we also managed to track down some of the makers and talk to them in about their projects.


We talked to Juan Sanchez from Team Tack, a group of designers from Tack Mobile, who spent the hack-a-thon making littleBits talk to the smartstrap, and built Pebblits.

The idea we were most excited about was trying to make it easy to use littleBits to prototype smartstraps. We use littleBits quite a bit for prototyping hardware ideas internally and with some of our clients. Having the ability to snap littleBits right into a Pebble Time was really compelling to us because you could potentially prototype 1,000’s of smartstrap ideas right on-the-fly. This also meant exposing the capabilities of smartstraps to a very broad audience, and even more beyond that, wearables in general.

The smartstrap is a really compelling opportunity, especially if you expand your thinking beyond a strap attached to the watch. The terminals for smartstraps could connect/dock to any kind of form factor. Yes, there’d have to be a compelling reason for people to take their watches off, but it’s interesting none-the-less.

Practically, we were able to get up and running really quickly. Our initial goal for our project was to be able to push a littleBits button and have something show on the Pebble Time screen. We met that goal the first day.

Altimeter Smartstrap

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We talked to David  Groom  and Bryan Thomas from Team Hack Dads who built the Pebble Altimeter Smartstrap, which won Best Pebble Integration at the end of the hack-a-thon.

We built an altimeter smartstrap and watchface with the idea that hang gliders, hikers, and other elevation-curious types could use their Pebble Time to measure and track their altitude.  In addition to actual number of feet above sea level, the watchface indicates whether you are above or below your previously measured altitude (i.e. ascending/descending), and if you tap or shake the watch, a real-time graph of the last 10 measurements is displayed.  Living in the Detroit area, Boulder’s mountainous landscape was an inspiration, and we thought an altimeter would be a fun sensor to base an idea around, and things just sort of flowed from there as we iterated on the base concept and shared it with others for feedback.  All the source and a how to recreate the smartstrap hardware, can be found on our wiki page.

The Survival Strap

The Survival Strap (Image: 23rd Studios)
The Survival Strap (Image: 23rd Studios)

We talked to Mike Cassano from Team Universal Mind, who built the SurvivalStrap, the project that won both People’s Choice and Most Technically Impressive at the end of the hack-a-thon,

We built a smartstrap called the SurvivalStrap — it was built using the Pebble Time + Arduino Uno + simple electronic components.  The goal of the hackathon was to hack on a serial port on the Pebble so we designed a circuit that when activated by an app on the Pebble would broadcast your GPS on public spectrums that search-and-rescue teams monitor.  A possible use case is you go hiking in the woods out of cell coverage, break your ankle and need evacuation.  The app also has rudimentary survival guides because you probably didn’t plan on needing to live in the woods for a day or two.  We also built a strap from paracord and fire starting material to aid survival.  The team was heavy on designers which was great because we needed to tell the story.

Pebble NFC Payments

The FitPay NFC Payments (Credit: Steve Kurtz)
The FitPay NFC Payments (Credit: Steve Kurtz)

Interestingly the hack-a-thon didn’t just attract makers, but also maker busnesses. We talked to Steve Kurtz from FitPay about how they used the hack-a-thon to develop a hardware platform for their payment platform.

We had been looking for a good opportunity to integrate our wearable payment platform with real hardware, and the timing was perfect. Also, our office happens to be in the space where the hack-a-thon took place, so it would have been more to difficult to not attend.  

We created a contactless tokenized NFC payment experience for the Pebble Time by combining a FitPay Pebble App with a hardware stack that included a secure element and NFC controller embedded in a Smart Strap. The FitPay team consists of a talented group of technologists with deep payment industry experience. For this particular event, we rounded out our group with a hardware expert and business partner from CONNECTEDEVICE.

By the end of the hack-a-thon the team had made the very first retail transaction using the Pebble Time.

How to Get Started with the Smartstrap

If you’re interested in getting started with the smartstrap a good place to start is the presentation given by Brian Gomberg at Pebble’s Wearable Meetup in San Francisco earlier this month. He covers all the important details, from protocol structure to example code, and shows off a live prototype

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Pebble have posted mechanical details of the strap along with assembly instructions allowing you to build your own, and well as documentation on the smartstrap protocol, how to talk to the smarstrap from your Pebble Time, and how to talk to the Pebble Time from the smartstrap. There is also an example Arduino library for communicating with the Pebble Time using the smartstrap port.

Of course if you do build your own Smartstrap, there’s the opportunity to dip into Pebble’s $1 million fund set up to encourage the development, and commercialization, of Smartstrap projects for Pebble devices.

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Alasdair Allan is a scientist, author, hacker and tinkerer, who is spending a lot of his time thinking about the Internet of Things. In the past he has mesh networked the Moscone Center, caused a U.S. Senate hearing, and contributed to the detection of what was—at the time—the most distant object yet discovered.

View more articles by Alasdair Allan