Totem Pop is an open source health tracker that gives full control on what data you want to save or share.


This project in 60 seconds

For our master graduation project, Stijn Zoontjens and I worked together on the development of an open-source health tracker. From research, we learned that most users stop using health trackers within a year of purchasing. Health trackers are designed to be used by a wide target audience, but often lack the focus to support people in the long run.

What we learned is that wearables could have a positive impact on patients. They have a clear need and medical support to benefit long-term from an intervention. The problem is that current solutions use proprietary algorithms that prevent access to raw data to address specific patient needs. Therefore researchers and developers have to reinvent the wheel using open-source projects that are bulky and complex to use.

In this project, we developed a wearable open-source health tracker that allows you to experiment and research within minutes. It can be easily set-up with an app but can also be used stand-alone for days. To support a variety of use-cases it can be extended with sensors. After exploration and research, the open-source software and hardware can be used to create custom solutions for patients.

My Role

Together we conducted research and defined the scope and direction of this project. I used the insights we gained to design the structure, flows and interactions within the app. In addition, I worked on designing and developing the electronics and hardware of Totem Pop.

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Although the market share of wearables has grown significantly over the past years, it seems like they haven’t reached their full potential yet. According to studies from Endeavor Partners and PWC in 2014, between 33 and 50 percent of people give up their devices within a year. Wearables at this moment do not seem to create enough value for people to use them for a longer period of time.

We worked together with academic researchers on the topic of behavioural change and interviewed human movement sciences and physiotherapists. Our research indicated that wearable health tracking can be especially of added value for patients. They have a clear need and medical support from professionals to use the intervention over a longer period of time. Most health trackers currently on the market are the exact opposite, they are designed to be generic and appeal to a wide target group. And due to their proprietary algorithms, their data can’t be used for research or the development of new use cases.


Our vision in this project was that researchers, designers and makers would be able to create new solutions tailored to the needs of different patient groups. We, therefore, set out to create an open-source health tracker that would give access to raw data and could be easily adapted to support different use cases.

Open-source products offer a lot of opportunities, but they are often hard to use and require a level of expertise in order to work with them. Our goal was to create a product that combined the accessibility of proprietary solutions with the limitless opportunities of open-source.

Design Principles

Based on our vision we came up with 4 principles to guide the design process.

1The product should work straight out of the box.

2The product should work without having to open the enclosure.

3The product can be adapted to different use-cases without the need for programming or soldering.

4The product should be small and needs to fit different parts of the body.


Interaction Design

The mobile app is designed to easily set-up the wearable and start experimenting. One of the challenges we faced was designing a platform which would give expert users the flexibility they need, while at the same time keeping it accessible to novice users. Below you find a few examples of how we approached this.


The 'recipe' is used as the container that contains all the settings of the tracker. The recipe structure is designed to address both expert and novice users. Novice users can start by using and adjusting pre-made recipes, while experts can start from scratch, customizing every detail to their liking. Users can have multiple recipes in their app and can sync them to the tracker by activating the recipe. 


In addition to setting up a tracker for data logging, users are able to visualize their data in real-time. Data from the individual sensors can be expressed in numbers or graphs, but the app also allows for using simple logic like thresholds and counters to give feedback to users. Researchers are easily able to create a simple dashboard for research participants or can decide to remove the dashboard completely to not interfere with the research study. 

New Visual

New visualizations can be easily created by giving answer to a few simple questions. Users are able to select a specific axis of a sensor but can also use for example the total acceleration of the tracker as input. The menu structure allows to easily change any of the previously made decisions.  

Totem Pop

Totem Pop has built-in motion sensors and can be easily extended with external analog sensors. This enables specialists and researchers to easily measure a wide variety of parameters, for example, the bending of the lower back or the pressure underneath the foot.

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Raw data can be saved locally on an SD-card or can be used real-time for processing on the phone using Bluetooth Low Energy. The internal battery can be charged with a USB charger and lasts up to 10 days. The different back covers can be easily exchanged to mount the tracker to different parts of the body or to equipment like bikes to support various use cases.

The Android app is made to help users explore the possibilities with the tracker. People can use the app to set-up the device and visualize and process real-time data to quickly experiment and learn.

Design Process

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Our focus in this project was on execution, focussing on developing the project to a level it could be easily continued by others. We developed a fully functional prototype consisting of electronics, industrial design and software. In the project my main responsibilities were the development of the electronics, industrial design of the tracker and the interaction design for the app. What I really enjoyed was the ability to dive deeper into these topics and work together with others to create an integrated and holistic project.

I hope you enjoyed this project.

How about looking at another one below?