## 4 Application and Results
### Phase 2-Collection of Related Articles Using Snowballing  
For this second phase of ERSA process, studies that were conducted in high-income countries were withdrawn from the selection to keep only low-income countries. The choice was made to include in this definition the African continent, South Asia (Bangladesh, India, Indonesia, Pakistan), and South America. A first set of articles was collected using this strategy. A filter was also applied to keep only articles published after 2018. Figure 4 depicts the results from the Research Rabbit process [29] when given the list of the articles collected during this phase on criterion (1), low literacy rate. Each node represents an article, while a connection indicates that there is a citation between two articles. Some groups of citations are formed at the top and bottom, while in the middle sits a set of articles that are not interconnected.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Criteria** & \
\begin{tabular}{c} **Low-Income Countries Versus** \\ **High-Income Countries** \\ \end{tabular} & **Baseline Studies** \\ \hline \multirow{4}{*}{1} & \multirow{4}{*}{Low literacy rate} & In low-income countries, illiteracy is & \multirow{4}{*}{[PERSON] [34]} \\  & & almost three times as high as in & \\  & & lower-middle and upper-middle income & \\  & & countries. The user interfaces based on & \\  & & text are therefore not suitable for users & \\  & & in low-income countries. & \\ \hline \multirow{4}{*}{2} & \multirow{4}{*}{Low level of computer literacy} & Low level of & Low levels of digital literacy. The user & \multirow{4}{*}{[PERSON] [34]} \\  & & level of & interfaces that assume users are & \\  & & proficient on using a computer are & \\  & & therefore not suitable for users in & \\  & & low-income countries. & \\ \hline \multirow{4}{*}{3} & \multirow{4}{*}{High rate} & As a whole, high-income areas have low & \multirow{4}{*}{[PERSON] et al. [35]} \\  & & linguistic diversity, while low-income & \\  & & areas have high linguistic diversity & \\  & & of multilingual & geographically. The user interfaces & \\  & & with oral languages & made for only a few major worldwide & \\  & & languages are therefore not suitable for & \\  & & users in low-income countries & \\ \hline \multirow{4}{*}{4} & \multirow{4}{*}{Impossibility to access IT tools} & In around 50\% of the low-income & \multirow{4}{*}{[PERSON] [36]} \\  & & countries, fewer than 50\% of inhabitants & \\  & & report owning a smartphone. Energy & \multirow{4}{*}{
\begin{tabular}{} \end{tabular} } \\  & & access is low in poorer countries, and & \\  & & increases as incomes increase. A decent & \\  & & internet connection is out of reach for 90 & \\  & & per cent of people in low- and & \\  & & middle-income countries. The user & \\  & & interfaces designed on devices that are & \\  & & not used and/or requires frequent & \\  & & recharging or high connection quality is & \\  & & therefore not suitable for users in & \\  & & low-income countries & \\ \hline \multirow{4}{*}{5} & \multirow{4}{*}{User culture} & As most user interfaces decisions are & \multirow{4}{*}{Heimgärtner [37; 38; 39]} \\  & & made in high-income countries, the & \\  & & need to understand the culture of & \\ \cline{1-1}  & & end user is utmost important. The user & \\ \cline{1-1}  & & interfaces designed with the culture of & \\ \cline{1-1}  & & the designers’ country in mind is & \\ \cline{1-1}  & & therefore not suitable for users in & \\ \cline{1-1}  & & low-income countries. & \\ \hline \hline \end{tabular}
\end{table}
Table 1: List of the baseline studies in each criterion. Each article has been selected as a reference in their respective criterion or in related user interfaces solutions to take into account the criteria.