# Comparative Vulnerability Analysis of Thai and Non-Thai Mobile Banking Applications
## 3 Materials and Methods
### Sample Selection  
This research focuses on identifying and comparing vulnerabilities in mobile banking applications. To achieve this, a purposive sampling strategy was employed. The target population for this study is defined as Thai mobile banking applications available for download on the Google Play Store.  
Within this target population, five popular Thai mobile banking applications, whose true identities are not disclosed in this study and are hereby called Bank A, B, C, D, and E, were chosen for in-depth analysis. All of them have achieved more than ten million downloads each on the Google Play Store. This selection was based on download numbers retrieved from the Google Play Store. By focusing on these widely downloaded applications, the research aims to gain insights into the vulnerabilities present in mobile banking applications commonly used by Thai users. All of these banks are also classified as national-level banks since they operate and have customers from all over the country. Moreover, the selected banks are similar in terms of total assets. Analysing these applications allows for a more practical understanding of the security risks faced by a significant portion of the Thai mobile banking population. Table 2 provides details of Thai mobile banking applications chosen for the analysis in this research.  
For comparative purposes, a group of mobile banking applications from other Asian countries was also included in the study. Although these banks' real names are not disclosed, we provide some details as a Chinese Bank, an Indian Bank, a Singaporean Bank, and a Korean Bank. The selection of these specific banks considered factors like regional representation and similar functionalities. They are also among the largest and most influential in their respective countries, and their mobile banking applications serve a significant portion of each country's mobile banking users. Including applications from geographically diverse locations allows for a broader understanding of potential vulnerabilities across the Asia-Pacific region. Additionally, choosing banks with functionalities comparable to the Thai applications helps to ensure a more controlled comparison, minimising the influence of variations in features on the types of vulnerabilities identified. This comparative study offers an initial analysis among the studied mobile banking applications and assesses whether Thai applications exhibit unique vulnerability patterns compared to their counterparts in other countries.  
Overall, our study aimed to compare the security vulnerabilities of mobile banking applications in Thailand and different Asian countries. Purposive sampling allowed us to deliberately select banks that would provide rich information relevant to our research questions. We selected banks with significant market presence in their respective countries. This criterion ensured that our study focused on applications used by a large number of customers, thereby increasing the relevance and potential impact of our findings. To enable cross-country comparisons, we purposefully included banks from different Asian countries. While we realised that this approach does not allow for generalisation to all banks in these countries, it should still provide valuable insights into potential differences in security practices across different markets. In addition, given the in-depth nature of our security analysis, purposive sampling allowed us to focus our resources on a manageable number of applications while still addressing our research objectives.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Application** & **Version** & **Size (MB)** & **Class** & **Asset (Million USD)** \\ \hline Bank A & 2.25.0 & 82.39 & National & 85,462 \\ Bank B & 5.19.0 & 127.00 & National & 110,935 \\ Bank C & 14.6.7 & 179.00 & National & 99,303 \\ Bank D & 3.34.1 & 103.00 & National & 116,384 \\ Bank E & 3.80.0 & 274.00 & National & 93,561 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Thai Mobile Banking Applications Used in this Research.