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Fitbit is an American company focused on digital health and fitness and was founded in 2007 by Eric Friedman and James Park. The company focuses on using sensor and wireless technology to better advance the experience to fitness and health. [1] The Fitbit company is most known for its smartwatch and tracker products. The products are usually worn on the wrist or are clipped to clothing and other accessories to help keep track of steps, workout sessions, heart rate, and quality of sleep. [2] The Fitbit company was completely acquired by Google in 2021. [3]

In looking at the ethical consideration of the product, Fitbit collects a great amount of sensitive data from the users and people are unsure about whether their personal data remains confidential. This concern increased after the Acquisition of Google. Some problems also arise with the tracking feature of the technology. People who use the wearable tracking feature may be involuntarily stalked or leak important geographical information. The device also has some concerns related to the security of the device and the potentiality of it being hacked. Furthermore, Fitbit data is still under debate on whether it can be used as evidence in court or not.

Fitbit Logo, from Fitbit website. [4]


Heart-rate monitor

Fitbit uses photoplethysmography in their technology to track heart rate. The new technology is named PurePulse. By monitoring the heart rate, it can help the user to achieve their weight goals, optimize their exercise routine and help to manage the stress levels. Photoplethysmography is a technology that uses light to measure blood flow. The volume of the blood in the users’ wrist will change when the heart beats. The blood can absorb green light. The higher one’s blood volume is, the more green light is absorbed. Photoplethysmography utilized this feature of the blood to calculate the blood flow by shining green light onto the skin. Then it uses light detectors to measure how much green light has been absorbed, it can then determine the heartbeat rate. [5]

Calories Burned

Fitbit devices combine the users’ BMR and activity data to estimate the amount of calories burned. This estimation can also be influenced by the heart rate data. The heart rate data have a heavy impact on estimation of calories burned during exercise sessions. The BMR data, which is also known as basal metabolic rate, is based on the physical data that the user entered such as height, weight, sex and age of the user. The data helps to estimate at least half the calories the user burns in a day since the body automatically burns calories even with daily activities. [6]

Sleep monitoring

Fitbit devices can help estimate the users’ sleep stages by using a combination of movement and heart-rate patterns. The device will assume the user is asleep if it hasn't been active for about an hour. Additionally, it can further confirm that the user is asleep by matching the length of time of movement to typical sleep behavior such as rolling over. While the user is asleep, the device tracks the changes in the user’s heart rate. This is known as heart rate variability. The heart rate will change as the user is going through different stages of light sleep, deep sleep and REM sleep stages. The Fitbit device will collect those data and compare them to the heart rate and movement pattern in the next morning to estimate a more accurate sleep cycle from the previous night.[7]


Image of the Fitbit Luxe, from Fitbit website. [8]


The Fitbit smartwatches currently includes three products: Fitbit Sense, Fitbit Versa 3 and Fitbit Versa 2.

Fitbit smartwatch cost a bit more compare to the Fitbit tracker. The product is a wrist bound device that contains a screen and is essentially an extension of the user's phone. The Fitbit smartwatch contains features such as time reading, messages and the ability to download third-party applications. It does not include features for making and taking calls.


Fitbit trackers are a simple device intended mainly for tracking and monitoring basic physical movement. The tracker is a band with a sensor that deliver data onto the user's smartphone. The device is physically smaller than the Fitbit Smartwatches and is relatively lightweight. They have a lower cost. The trackers does not work with third-part applications.

Fitbit currently carries: Fitbit Charge5, Fitbit Luxe, gorjana for Fitbit Luxe Special Edition, Fitbit Ace 3, Fitbit Ace 3 Special Edition: Minions, and Fitbit Inspire 2.


Fitbit provides a premium monthly membership plan. The service includes a three month free trail before charging monthly membership fee. Some of the features of the service includes guided audio and video work out classes, mindfulness session such as yoga session and meditation classes, access to a great range of healthy recipes and fun health challenges to help the users stay engaged.

Smart Scales

Fitbit smart scales series only has one product which is Fitbit Aria Air. It is a smart scale that can display user's weight and it can be synced up with the existing Fitbit user's data and account. The users can log into their account to view their BMI and tracks the trends overtime. It also supports multiple users use and tracking different user profiles.


Fitbit provides various accessories for their trackers and watches. Most of the accessories are in the form of different design of bands to provide the smartwatch or tracker a better personalized look. The accessories also includes all the charging cables for all the existing models.

Ethical Issue

Data Security

  • Before Acquisition

Fitbit collects an extraneous amount of data. This includes the sleep cycle, heart rate, steps count, weight, food intake, exercise and devices owned by the users. From the data collected, Fitbit device can also derive the time of a user from being awake to going to bed, the time zone that the user is in and the IP address of the user. These data, according to the privacy policy of the Fitbit company [9], may be shared in a way that is aggregated or de-identified and non-personal. “For example, in public reports about exercise and activity, to partners under agreement with us, or as part of the community benchmarking information we provide to users of our subscription services.” Fitbit also includes that the data may be shared when asked to share by a user through a third-party such as an employee wellness program. Fitbit’s privacy policy states that they will not sell any personal data but later on in the policy, Fitbit states that some data is used for marketing. According to a Fitbit spokesperson, Fitbit never sells personal data and we do not share customer personal information except in the limited circumstances described in our privacy policy. Our business model is not based on advertising. We do not target users with third-party ads. Like many others, we advertise our own products and services and work with advertising partners who help us with this. We disclose this in our Privacy Policy and explain to users what their privacy options are.” [10]Fitbit also stated in the Privacy Policy that they will share information with the law enforcement when required by the law. However, Fitbit does not publish any warrant canary to inform the users that the provider has been served with government subpoenas.

  • After Acquisition

On November 1st 2019, Google announced the plan of acquiring Fitbit for $2.1 billion in order to advance its hardware business within the healthcare space. During the acquisition, Google explicitly stated that they will not sell any personal or health data. People are having a hard time believing this announcement. The public felt more insecure when Google paid its data privacy fines in the EU in order to enter the stringently relegated healthcare market. The company received some pushback from privacy groups which delayed the closing of the acquisition from early 2020 to 2021. [11]

Tracking Controversy

  • User Tracking
Theoretically, it is possible for Fitbit users to use a combination of basic data on the device to track a user. The user could use a combination of location data, the timezone of the user, the time of the day, and steps counts to make a prediction where a user could be located.[12]
  • Geographical Tracking
Fitbit technology, like other fitness-tracking technologies, uses GPS to track and record a user’s exercise activity and allows the user to share the information with other users. Fitbit also allows the users to download and use third-party apps on their devices including fitness app Strava. In 2018, Strava released a heat map that highlighted all the routes of the users which includes running and bike riding paths. This caused controversy since military personnel on active service are also using the app. The tracking of the wearable technology made the location such as military bases clearly identified on the heat map. This not only includes the outline of the location but also the internal layout of some of the larger bases which is mapped out by tracked jogging routes of numerous soldiers[13]. This could lead to exposing sensitive locations especially with the locations mapped out in war zones and deserts. The heat map is almost entirely dark in the war zones and deserts in countries like Iraq and Syria besides the scattered points of activity. Those activities can bring focus to the location and outline of the U.S. military bases and other unknown and potentially sensitive sites. The heat map is available to everyone which means anyone can receive the information of how a user is moving along with the speed and frequency of the user’s activity. The military is currently revising the guidelines on the use of all wireless and technology devices on military facilities as a response to the result of this revelation[14].

Device Security Risk

According to a study, Security Analysis of Wearable Fitness Devices(Fitbit), done by MIT researchers Britt Cyr, Webb Horn, Daniela Miao, and Michael Specter, Fitbit provides a reasonable level of privacy for user data. However, the study also shows that the Fitbit devices were assigned a private address and this address does not change. This can potentially lead to unauthorized tracking through the person’s Fitbit’s bluetooth. This can also lead to attackers extracting the authentication key between the Fitbit device and smartphone or computer application which can result in launching a replay attack over bluetooth. During the process of pairing the fitbit device to the user’s phone, the phone can detect all fitbit devices within a certain range. This can raise some security concerns for finding or pairing wireless devices that do not belong to the user. The researchers also found that Fitbit device sends over Javascript to the phone, this may leave room for the attackers. Although the general security setup of the Fitbit devices is decent, there are some possible rooms that may yield unknown attacks. [15]

Court Evidence

Courts are overwhelmingly deciding that Fitbit and other wearable devices might be a quantifiable aid in the quest to find the truth. In some past court cases, Fitbit data was proven to be more truthful over human reporting. In 2015, Connecticut resident Richard called 911 and claimed that an intruder had broken into their house and shot his wife Connie and tied him to a chair. However, Connie’s Fitbit tracker told a completely different story. At a time that Richard claimed Connie had already been shot, Connie’s fitbit tracker was still tracking her movements. To further solidify this evidence, a local surveillance footage showed Connie’s visit to the gym during that time. The Fitbit data was strong evidence because it created a timeline that contradicted Richard’s statement [16].

In 2018, another court case used Fitbit data as strong evidence in a murder case. A 90-year-old visited his stepdaughter and her body was discovered by her co-worker 5 days later. Data from her Fitbit devices showed a “significant spike” in her heart rate during the man’s visit followed by a “rapid slowing”. 5 minutes after the men left her home, her heart rate stopped. The police arrested the stepfather based on a combination of video surveillance and assistance from Fitbit[17]. In both these court cases, Fitbit data was not used as the main securing evidence but rather an important assisting evidence. The utilization of the Fitbit data may prove to be a bigger shift towards “truth” powered by pure data. It may seem that having evidence that can not lie in court is an extremely useful tool but the data is not accepted in every situation in court.

Despite these cases demonstrating a positive effect of the Fitbit data, the higher court has dismissed the appeal over the fitbit data. The uncertainty behind the data can tell a different story from the truth, which leaves doubts for the device’s function and reliability. The data from wearable technologies can sometimes be forged with a different functionality. It requires a lot of analysis of the data to ensure that the data is useful for the case and not to be confused with other normal daily activities. According to some of the counsels at Electronic Privacy Information Center and contributors to “tracker and the law”, it does not seem like wearable technology data will be accepted in the higher court anytime soon. But the Electronic Privacy Information Center did claim that the healthcare system may actually assist the legal system with establishing the reliability of wearable data. This is because the healthcare system is getting more involved and serious about evaluating the accuracy of wearable data and an increased use of trackers in research and clinical use. If the tracking information starts to get adopted in the medical record, it might be the start of using wearable data information in court cases[18].


  4. "Fitbit Logo." <>.
  8. "Fitbit Documentation." <>.