# Investigating Wearable Fitness Applications: Data Privacy and Digital Forensics Analysis on Android
## 3 Methodology  
The National Institute of Standards and Technology (NIST) is the premier organization for establishing acceptable measurements, standards, guidelines, and procedures for various products, systems, and technologies (2019). NIST has published guidelines on conducting mobile forensic investigations and identified the four broad steps of mobile forensics, such  
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as (1) preservation, (2) acquisition, (3) examination and analysis, and (4) reporting. The authors have followed these steps in conducting this study, as detailed below. The authors investigate these wearable technologies from two sides: (1) identify forensically relevant artifacts from these three fitness apps to aid forensic investigators in investigations and (2) highlight any security and privacy concerns of the data being stored by these three apps on an Android device. The first side requires us to focus on what forensically relevant data can be recovered from within these apps on an Android smartphone. Mainly, the authors focus on any recovered data that may be useful to corroborate or disprove someone's alibi during an investigation. These data may include the user's heart rate, sleep data, activity data, GPS locations, app notifications, and voice data. The second side of our investigation requires us to identify any privacy leaks and security issues within these apps that may be troubling for these fitness apps' users. Particularly, the focus is on highlighting any users' personally identifiable information (PII), such as the user's entered profile information (including name, email, and date of birth) and voice data (in regard to the Amazon Halo Band). Before we were able to start the data population, we needed to prepare our test smartphone device. We chose to use a Samsung Galaxy A50 smartphone running Android 10 as Android 10 is one of the newer and most prevalent mobile operating systems being used today. In June 2021, Android 10 had a market share of over 36.5% among all mobile Android devices worldwide [20], making devices running Android 10 likely to be included in a forensic investigation. The A50 smartphone used in this study was already rooted prior to beginning the investigation. The rooting process ensures that we get privileged access to the user data partition/filesystem of the device, which stores the most relevant forensic artifacts. As such, to avoid future rooting woes, we decided to begin this study without the first factory resetting the device. To begin, we ensured that the smartphone device was rooted using the Root Checker Android app [21] after which we were ready to start device linking and data population. Table 2 presents the smartphone device information along with the three selected wearable fitness devices. Regarding possible data types, all three wearables included multiple sensors. The Amazon Halo Band includes an accelerometer sensor, a temperature sensor, a heart rate monitor, two microphones, and a LED indicator light [22]. The Garmin vivosmart(r) 4 fitness tracker includes a Garmin Elevate(tm) wrist heart rate monitor, barometric altimeter, accelerometer, ambient light sensor, and a pulse OX blood oxygen saturation monitor [23]. The Mobvoi TicWatch S2 contains an accelerometer, gyroscope, heart rate sensor, and a low latency off-body sensor [24]. Figure 1 depicts the three fitness devices used in this study, Figure 2 highlights the steps followed in this research, starting with the design of the experiment and ending with the reporting, and Figure 3 illustrates the communication protocols and software tools used in the study. Furthermore, in the following subsections: Section 3.1 Data Population, Section 3.2 Acquisition, and Section 3.3 Analysis, we detail the methods and tools used to conduct this investigation in a forensically sound manner across the experiment phases.