> fail to see how my basic health data like HR, weight etc is going to be used against me except for bad marketing practices. I actually looked into this in so

> fail to see how my basic health data like HR, weight etc is going to be used against me except for bad marketing practices. I actually looked into this in some (limited) detail, although for a slightly expanded definition of all data a Fitbit (and the near future similar devices) could collect. Heart rate data has been used in legal cases in the past. In an insurance fraud case, heart rate data from a pacemaker was used to provide evidence the events could not have occurred as described [1]. Similarly activity data has been used to defend against a false rape claim [2]. There is no reason such data could not be used in any other legal case. The data collected by such devices can also reveal much more information about yourself than most think. By watching hand movements via accelerometer, smokers can be identified with 95% accuracy [3]. Users can be tracked via Bluetooth identifiers, or via the unique walking pattern of each individual [4]. Even when encrypted, users can be identified by the frequency of communication to the smartphone. Furthermore, pins can be identified by monitoring users hand motion via accelerometer [5]. For more advanced next generation fitness trackers tracking your ECG, this has been shown to be as unique as a fingerprint, allowing individuals to be uniquely identified across devices [6]. There is no reason that this data could not be used against you via insurance companies to change insurance costs (smoker, type of transport, heart health, activity) or even force you to wear one much like some car insurance requires black box monitoring. You could be taken in for insurance fraud by saying you are not a smoker, or it could potentially be used against you in court. This data can also be falsified, meaning fake data could potentially be used against you. In summary, there are many other privacy problems with fitness trackers. [1] https://apnews.com/c55eac83846f42e19fb924e57917001b https://apnews.com/c55eac83846f42e19fb924e57917001b [2] https://blogs.findlaw.com/blotter/2015/07/can-your-fitbit-data- https://blogs.findlaw.com/blotter/2015/07/can-your-fitbit-da... be-used-against-you-in-court.html [3] https://www.researchgate.net/profile/Ilaria_Torre/publication/316925412_Fitness_Trackers_and_Wearable_Devices_How_to_Prevent_Inference_Risks/links/5a98a064aca27214056d5641/Fitness-Trackers-and-Wearable-Devices-How-to-Prevent-Inference-Risks.pdf https://www.researchgate.net/profile/Ilaria_Torre/publicatio... [4] https://www.dailydot.com/layer8/fitness-trackers-open-effect-citizen-lab-report/ https://www.dailydot.com/layer8/fitness-trackers-open-effect... [5] https://www.stevens.edu/sites/stevens_edu/files/ChenWearablesPaper.pdf https://www.stevens.edu/sites/stevens_edu/files/ChenWearable... [6] https://www.sciencedirect.com/science/article/pii/S0031320304002419 https://www.sciencedirect.com/science/article/pii/S003132030...