User Centered Scenario Based Approach for Developing Mobile ...

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User Centered Scenario Based Approach for Developing Mobile Interfaces for Social Life Networks

Pasquale Di Giovanni, Marco Romano, Monica Sebillo, Genoveffa Tortora, Giuliana Vitiello

Lasanthi De Silva, Jeevani Goonethilaka, Gihan Wikramanayake

University of Salerno, Italy {pdigiovanni,marromano,msebillo, tortora,gvitiello}@unisa.it

University of Colombo School of Computing Colombo, Sri Lanka {lnc, jsg, gnw}@ucsc.lk

Tamara Ginige

Athula Ginige

School of Business, Australian Catholic University North Sydney, Australia [email protected]

School of Computing Engineering and Mathematics University of Western Sydney Australia [email protected] providing real-time, context-sensitive local information by aggregating information from a variety of sources including SMS messages, sensor data and data from public data sources such as meteorological data [3].

Abstract—In recent years the explosive growth of smartphones and the evolution of mobile communication networks have certainly revolutionized the way how people communicate and access information. This revolution is even more tangible in developing countries where mobile devices are becoming the preferred way to access services for their daily activities. In this context, the development of mobile applications in the areas of health, education, agriculture, and mobile banking become a crucial factor. Unfortunately, the development process presents non-trivial human and technological challenges. The goal of our research is to support people living in developing countries to improve their lives. In particular we focused our attention on assisting farmers from rural zones of Sri Lanka in optimizing their crops.

This aggregated information can provide real time information on evolving situations such as market prices, how to manage pests and bugs destroying the crops, good locations to catch the fish under current climatic conditions, thereby providing just-in-time assistance and support for their livelihood. Yet there are many research challenges that need to be resolved before such applications can be successfully developed. One major research challenge is to develop a suitable user interface for mobile devices. When developing these interfaces in addition to the required functionality we need to factor in the users level of literacy, familiarity in using the device, users cultural background, language beliefs and the sophistication and functionality of the mobile device user can afford.

Keywords-User centered design, User study, System usability, Mobile interfaces, Developing countries, Social computing

I. INTRODUCTION There has been an explosive growth in the area of mobile communications in the last few years. Today nearly 5 billion people use a mobile phone; over 3 billion of them live in developing countries. Majority of current mobile applications have been developed to meet the needs of the 1.5 billion living in developed countries. People in developing countries need applications that can assist them with their livelihood in areas such as prevailing market demand and prices of a variety of products and services, assistance with farming, fisheries micro-banking, healthcare services and emergency response [1].

In this paper we report our investigation into developing a suitable user interface for a Social Life Network application using scenario based approach of Rosson and Carrol [15] to be used by farmers in Sri Lanka and how we addressed some of the above mentioned challenges. II. RELATED WORKS In recent years, a growing number of researchers have identified initially call phones and later smart phones as an ideal platform for developing applications for people in developing countries [1].

Using the enormous reach of mobile phones equipped with myriads of sensors such as GPS, Camera, microphone etc it is now possible to develop the next generation of social networks known as Social Life Networks that not only connect people to people, but also have the capability of

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UsARE 2012, Zurich, Switzerland

We used a scenario based approach to analyze the survey findings, combined with the wider context to gain insight into farm activities during the sowing and selling times of crops.

Mehdi et al. [4] focus their attention on mobile phones as a platform for the use of financial services by non-literate people. In particular, they focus on how to design mobile phone interfaces such that non-literate and semi-literate users can use financial services. They have observed that non-literate and semi-literate subjects were unable to make sense of text-based UIs. The task-completion rates were better for the rich multimedia UIs, and when spoken dialog was added to the UIs it reduces the task completion time as well as required less assistance.

Based on the survey findings we were able identify some of the factors that contribute to the oversupply of a crop. The scenario based analysis assisted us to identify the 1. 2. 3.

Danis et al. [5] begin their work observing that in the SubSaharan Africa there is an average ratio of one doctor for every 20.000 people. This challenge involves the need of new health approaches that are focused on prevention rather than treatment. Hence they analyze two deployments of an SMS-based HIV/AIDS education system that uses a quiz format to assess people’s knowledge of the disease, including its causes and methods of prevention. In particular they first focus on the challenges that the use of SMS present as user interaction mechanism and later explore factors that influence participation in quiz games. The paper shows that mobile devices are suitable means for spreading culture in rural countries.

the different actors involved the physical environment where they operate how they interact with each other during the whole process

Using these insights we designed the UIs for a mobile application to inform the farmers on prevailing supply and demand situation for different crops. A. The Context of the Study Sri Lanka has a tropical climate and rich soil. This has made agriculture the most dominant sector in Sri Lankan economy. Around 32.7% of the labour force is employed in the Agriculture sector [12], which is a significant percentage with respect to other sectors. Thus, the necessity to focus on this community, identify existing problems associated with farming and develop solutions using the existing and emerging technology is a vital for the sustainability of this sector.

Putnam et al. [6] discuss a case study aimed at identifying user requirements of mobile phone users living in Kyrgyzstan. During the study they identify a tenable mobile phone product concept; develop a working prototype of the concept and perform some usability testing. The process presented in this research work can be used as a guideline to develop user-centered solutions for different kinds of users, including those living in developing countries.

The government of Sri Lanka plays a significant role in this scenario to contribute towards an economic growth by promoting agriculture in various directions. The Department of Agriculture (DOA) whose main focus is to “achieve an equitable and sustainable agricultural development through development and dissemination of improved agriculture technology” [13], invests heavily on the farmer community to attain this mission. Conducting awareness seminars, providing seeds and subsidiaries for a nominal cost and establishing new acts and regulations are some of such services rendered to the farmer communities. However, though such processes have been carried out for the last few years, still farmers face difficulties at different stages in their farming career causing frustration and poverty.

Jayaweera and Senaratne [7] describe, in their work, a mobile service portal useful for Sri Lankan fisher communities concentrated mainly in rural coastal cities. The paper shows how an affordable technology, such as the mobile one, can be used to improve everyday life in developing countries. III. IDENTIFYING APPLICATION REQUIREMENTS Mainly the goal of our research was to develop a usable and useful mobile user interface to help Sri Lankan farmers improve their rural activities and gain higher incomes.. In order to achieve this aim, we followed a user-centered design approach: we studied potential users and included them in the initial conceptual design activities.

One such major issue is the low market price due to the excess supply of the harvest. Due to the low income, there were incidents where they tend to commit suicide being unable to pay their debt, as farming is the main source of income that they depend on. In the current context, farmers mainly depend on the basic knowledge gained from their fore-parents. Type of the soil, seasonal weather, water availability, financial status, pest and disease issues, play a vital role in selecting crops for cultivation. Though, farmers have a better understanding with respect to the different types of crops that can be grown on a particular season, they

This approach starts by studying users and existing solutions paying attention to their needs at each stage of the design process. Therefore, this research work has evolved from a survey conducted with real stakeholders to investigate the possible causes for an oversupply of agricultural products, which is giving rise to a drastic lowering of selling prices when products are sold in the markets in Sri Lanka.

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towards the market price of the previous year and they tend to select crops that produce a high yield within a short time period. Thus truck farming is quite common. None of the interviewed farmers had a specific land extend per crop in mind at the time of cultivation, though they have a better understanding about the different types of crops that can be grown on a particular season. This knowledge is gained mainly based on the practical experience that came via ancestors. During the study it was further identified that farmer awareness with respect to what others grow is limited to the neighboring farmers. This is mainly gained by seen what others are growing. They were reluctant to get this awareness by formal communication due to social phobia and the competition among farmers.

tend to cultivate crops that produce a high yield within a short time period with the intention of getting a good profit. On the other hand, market price of the previous year also plays a significant role in this aspect causing oversupply as most of the farmers unknowingly select the same crop for cultivation. There has been a tremendous growth in mobile phone usage in Sri Lanka for the past few years. According to Telecommunications Regulatory Commission of Sri Lanka, the number of Cellular Mobile Subscribers at the end of December 2010 was around 17,359,312 [14], which is around 80.95% of the total population proving the fact that it has become a part of the daily lives. Even the farmers in the rural areas, irrespective of their native language, tend to carry a mobile phone to the farm, and use it in their day to day activities.

It was further identified different selling mechanisms are adapted by farmers in Sri Lanka. Some have taken the harvest directly to the market, while around 90% depend on a middle person; the transport agent or the shop keeper. However, none of them got help from the government to sell the harvest. Another most interesting fact that was discovered is the behavior with respect to the selling price. The selling price is a dynamic value which changes instantly at a particular market. According to the farmers, it was said that they were unable to predict the price as it changes vigorously within few hours.

Like in many developing societies, a significant gap in access to ICT (digital divide) can be observed in Sri Lanka, especially among the rural sections of the society. The Nenasala Telecenter project was launched as part of the “eSri Lanka” initiative by the Government of Sri Lanka to reduce this divide. Telecenters are seen as the first step in extending the benefits of ICTs to marginalized groups and ultimately increasing economic growth, improving the quality of life and reducing poverty.

However, it was revealed that, according to their experience, they were unable to gain a good price for their harvest at the market, when all farmers tend to grow the same crop at the same time. As a result, according to the farmer from the Dambulla district, most of his neighboring farmers have given up farming and have joined other industries to find their living. This might have a huge impact for the economic growth of the country if this trend would continue further in the future.

The aim of Nenasala project is to establish 1000 centers throughout the country which provide access to Internet, email, telephone, fax, photocopy, computer training classes and other ICT services with a view to significantly increase the level of economic activity in rural communities, raise levels of computer literacy among children and adults and enable rural populations to access government information and services online. So far 629 centers have been established under this project [13]. The capability of such telecenters based ICT interventions to satisfy farmertargeted information needs is questionable especially from the perspective of easy access, scalability and economic sustainability of the operation. Steady growth of mobile phone usage in Sri Lanka offer hope for a mobile based intervention to up lift farming communities.

C. Scenarios of Current Practices Based on the knowledge gained from the survey, we envisaged a scenario of truck farming practices, from which we could start our brainstorming activity for the formalization of initial requirements and the design of a possible solution. Based on that knowledge, we defined two personas, representing possible stakeholders (Table I). D. Application Requirements The proposed scenario of existing working practices gave us the opportunity to reason about what were the major requirements that emerged from the rural Sri Lankan context. At this stage, we were primarily interested in deriving a list of farmers’ requirements that we could take into account throughout the design process. Summing up all the considerations and discussions we had upon the fieldwork completion, and reasoning on the derived scenario, we were therefore able to elicit an initial set of requirements divided into five categories according to the classification described by Preece et al. [9]. Table IV explains the rationale for each requirement.

B. The Survey Findings: the Cultivation in Sri Lanka The cultivation pattern of Sri Lanka is bi-modal. This is mainly due to the two monsoons, which bring rainfall to the island in two distinctively different periods resulting in the two distinct cultivation seasons. From the survey, it was noticed that due to this distinction there are specific crops to be cultivated in each of these seasons. Other factors that contribute to the crop selection are type of soil, weather, water, financial status, pest and diseases. Farmers are used to select crops for cultivation primarily based on the profit. As a result they are biased

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TABLE I – ACTORS INVOLVED IN THE SCENARIOS AS STAKEHOLDERS

TABLE III – CLAIMS FROM THE SCENARIOS OF CURRENT PRACTICES

Actors Sirisena is a 45 years old farmer with long experience in truck farming. Sirisena is part of Sinhalese ethnic group. He has a basic education level; he attended the primary school, he can read and write Sinhalese and he has a basic knowledge of English. Sirisena does not have advanced technical skills, the only technological instrument is his mobile phone that he uses everyday. Moreover he is pretty distrustful of the technological support and, during his work, is accustomed to rely on his farmer experience. Sirisena lives in Sigiriya, a village in the central Matale District of Sri Lanka, where he owns a four acres of farm land. Since the property is quite large, Sirisena in his work is supported by eight collaborators. Since Sirisena has a long experience in truck farming he manages the crop production of his family farm. His role is to make decisions on critical aspects of the production. He takes decisions on the kind of production and the time to start it. Moreover he establishes an indicative selling price.

1.

2.

Claims Situation features The farmer selects the crop cultivation on the basis of : 1. The period of the year 2. The crop producing high yield within a short time 3. The crop selling prices of the last year.

The selling price is fixed when the middle man gets the local market and estimates it on the basis of competitors’ products.

Premasiri is a 40 years old low price fertilizers seller. Like Sirisena, Premasiri is part of the Sinhalese ethnic group and lives near Sigiriya. In order to raise his revenues he also acts as market middle man. Since he can speak English as good as Sinhalese and has a basic knowledge of Tamil, his intermediary role is well recognized by the farmers of the area. During the market activities his responsibility is to negotiate the best selling price of the product trying to match the expectations of his clients.

E. Scenarios Transformation From the above analysis we identified a software application aimed to assist farmers in diversifying the crop production can assist to avoid selling prices of crops changing vigorously in few hours. Since users are distrustful of technology with the exception of mobile devices, developing a mobile application seems to be the right direction. The application should receive geographic coordinates of the users’ location of the farm and should provide them with valuable information about the kinds, the quantity and last selling prices of neighboring crops. Users may use this information in selection of crops for cultivation. The idea behind this application led us towards our scenario transformation activity (Table V). Based on the described activity scenarios we had some brainstorming meetings to identify the most important design claims.

TABLE II – SCENARIO OF CURRENT PRACTICES

Scenarios 1.

Sirisena manages the crop production of the farm

3.

Sirisena is planning the new crop production. The decision will be made on the basis of three factors. He takes in to account: 1. the period of the year 2. the crop producing high yield within a short time The crop selling prices of the last year Since the period of the year is suitable for potatoes cultivation and it gives the highest yield in a short time, Sirisena decides to produce mainly potatoes. Anyway, Sirisena makes his decision without interacting with his neighbors because he does not trust them. Three months later the crop is ready to be harvested. he establishes an indicative price of fifty rupees for one kilogram of potatoes, on the basis of the last year selling price and the expenses incurred during the cultivation period.

Design claim 1. By retrieving the field coordinates provided by the integrated GPS module, farmers access only information about estimated quantities and the last selling prices of neighboring crops. This allows farmers to select the appropriate crops in order to provide a larger variety of products and to make selling prices live up their expectations.

Sirisena does not have means to take the harvest to the market and moreover he could not well communicate with potential tamil buyers because of his language limitations. He decides to call Premasiri asking him to mediate during the market activities. 2.

Pros (+) and Cons (-) + The process knowledge is transmitted from father to son as cultural heritage + Cultural level of Sri Lankan farmers is enough to perform basic computations - The choice is based on a few factors without considering the neighboring crops that are paramount in the market business - The way farmers make decisions provides clients with a little variety of products. - over supply may result from this strategy + The production is oriented to the local market economy - the selling prices of crops change vigorously in few hours .

Premasiri acts as middle man to get the harvest sold Premasiri agrees to sell Sirisena’s harvest to the local market. Before starting the market activities all the farmers decide to raise or reduce the estimated harvest prices considering the presence of competitors. Premasiri notices that many farmers have cultivated large amount of potatoes. He is forced by the local market-law to reduce the estimated price cutting his profit. Moreover he notices that just a few farmers are selling onions so that the onions prices are noticeably higher than the last year prices.

Design claim 2. Data presentation should be provided in easy and immediate way exploiting the communicative power of images and color language. This allows small screen of the mobile device to provide users with complex information. Design claim 3. The interface should provide users with a small number of menu levels and operations. Farmers use the application just few times a year so that they need to be able to use the application without requiring a long training effort.

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TABLE IV – FUNCTIONAL AND NON-FUNCTIONAL SYSTEM REQUIREMENTS

TABLE V – SCENARIO TRANSFORMATION ACTIVITY

Scenarios

Functional requirements The application allows the By sharing valuable information exchange of heterogeneous data on crop cultivations, users would between neighboring users. be able to make better decisions guaranteeing anonymity. during the crop selection activities. Furthermore, because of social phobia and the competition among farmers, users are more conformable by preserving anonymity.

1) Even Sirisena is distrustful of technology is persuaded by a Nenasala officer to experiment a new mobile application aimed to assist selection of crops. Sirisena has been persuaded because of his familiarity with mobile devices and because he has been reassured about the nonintrusiveness of the software. Before starting to use the new application, Sirisena attends a one-day training course in the Nenasala center. Now Sirisena is ready to start planning the new crop production assisted by the new system. He gets to the farm, launches the crop assisting application and sends coordinates of the farm location. The application then informs him about the neighboring crop productions.

Environmental and contextual Requirements The application could be used in Users might be using noisy rural a noisy environment instruments or they might be speaking with co-workers while using the application in the field.

The decision will be made on the basis of few factors. 1) the period of the year 2) the crop producing high yield within a short time 3) last year’s market prices 3) types of crops that grow in the area

The environment could be sunny, rainy and powdery.

The application is used manly in open environments in particular in agricultural areas that can be really powdery.

Despite potatoes are suitable for the current period of the year and they give the highest yield in a short time, Sirisena notices that their production is already high in the area.

Users may need training provided by experts

Users are not in habit to work with advanced technological instrumentation. Therefore, they may need training .

In contrast onions production is pretty low and the last years selling price did not live up to expectations. This is because of the overproduction at the time. Therefore Sirisena decides to produce onions hoping the selling price can live up to his expectations. Based on the first three factors, potatoes seem to be the best choice, but the forth factor leads Sirisena towards a different direction.

Data requirements The application has the access to Farmers are interested to get data related to the distribution of information just about crops located around user’s farm. neighboring crops that are supposed to be sold to the same market. Data must be accurate updated frequently.

Four months later the crop is ready to be harvested., he establishes an indicative price of fifty rupees for one kilogram of onions, on the basis of expected selling price of the last year and the expenses incurred during his work. Sirisena contacts Premasiri asking him to get the harvest sold.

and

Users make crucial decisions on the basis of provided data. User profiles Most users will be in the range of 20 to 45 years.

2) Premasiri gets to the market and checks the variety of the present products. He notices that vendors provide a large variety of vegetables. The variety of the market allows him to save the selling price estimated by Sirisena.

The range of the instruction level varies between Ordinary Level and Master Degree. A large number of people can speak English well enough. Most users are not familiar with technology, with the exception of mobile phones that are quite widespread.

IV. DESIGNING MOBILE USER INTERFACE In the present section we describe the interface user requirements we used to address our design. Then we present the information architecture of the mobile application. Finally we describe the interface prototype that we developed in order to meet the interface requirements and the system functionalities. Starting from the scenarios, claims and application requirements we derived a list of interface requirements that we used to address the design of our application. We categorized them in two separate categories namely: a) data presentation b) data entry

All of the information is carried out from the initial survey conducted directly in situ.

Users are disposed to use some technological instruments on condition that they are not invasive. Usability requirements The application should be easy to The application is used manly in use and should require a little specific and not frequent tasks. training effort. The user interface should be effective: it should provide a simple management of users mistakes.

Table VI describes the two categories of user interface requirements and gives the rationale behind each of them. The two categories cover the two aspects of a traditional user interface. The former is related to the information output that has to be clear and fully comprehensible for users of different cultural levels; the latter is related to the input modalities; indeed, this stage can be really hard and

The application provides support to a critical task on the basis of data updated directly by users. Therefore, it is paramount to reduce the number of possible unintentional user mistakes.

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annoying for users and can lead users to make mistakes as described in [11]. TABLE VI – INTERFACE REQUIREMENTS UI Functionality

Rationale

Data Visualization list of products, each one associated with a significant icon. a visual colored cue associated to each product to indicate the estimated harvest quantity.

Interface provides users with language support, both in text and audio forms.

At any cultural level the user is able to quickly identify the visualized product The visual cue is needed to inform a participant of the quantity of a given product of the list. It provides an intuitive way to understand the magnitude of the quantity. Interface can exploit the multimodality in order to guarantee the right comprehension of the information in each situation. For example when the user is semi-literate or when he is working in a sunny or noisy environment.

Data Entry Interface avoids requiring text input. Whenever it is possible multiple radio buttons are used. Interface limits the number of interactions, hiding operations that can be automatized.

Text input is a common annoying source of mistakes. Radio buttons are easier to interact with. Some operations require unnecessarily user interactions exploiting the advanced device features.

Figure 1 describes the information architecture of the mobile application. As a first step the application requires users to log into the system. Next the geographical coordinates of their farm location need to be provided. These are two technical steps are very much prone to user errors. After these two steps users reach the crops catalog and select the desired product. Once they select the product a new view of the interface allows them to insert the planned quantity of the crop.

Figure 1 – Information architecture of the mobile application

Interface Challenges In this subsection we describe the interface prototype we developed in order to meet the interface requirements and the application functionalities. Meeting the “Data Entry” requirements described in table VI, we decided to automate the first two steps of the workflow (Fig. 1): 1. The authentication step is automatically performed by using as log-in credentials the mobile phone number stored in the device. 2. The field position is automatically retrieved by using the integrated GPS receiver and sent to the system.

Figure 2 – The application asks user to wait for automatic retrieval of coordinates and user credentials

Figure 3 describes the crops catalog. Here the design meets the “Data Visualization” requirements. The catalog is divided into crop categories. Opening a category page triggers a verbal description of the category. We use icons to describe crops and a colored background to indicate the approximate quantity of each crop already in production.

Figure 2 shows the application waiting the finalization of the first two steps.

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living in countries with a cultural background similar to Sri Lankan one. The next steps of this research will consist in - performing a usability field test with farmers in Sri Lanka in order to prove the effectiveness of the initial solution. - collecting further requirements, directly related to other stakeholders, such as the middle man, whose selling activities could be enhanced if informed decisions could be made in advance.

The color scale ranges between white = Zero production and red = Intensive production. A local language text label is added to each icon. By selecting the product users reach the last step of the workflow described by Figure 4.

REFERENCES [1]

[2]

Figure 3 – The crops catalog

[3]

Opening the new page users receive a verbal description of the selected product. Users are provided with a more detailed description of the product. By taking into account data entry requirements we provided check box items to allow users to insert information about the quantity of product that they want cultivate without typing errors.

[4]

[5]

[6]

[7]

[8] [9]

Figure 4 – Product selection interface

[10]

V. CONCLUSION

[11]

The development of mobile applications is paramount to support users living in developing countries to improve their lives. One of the major research challenges is to develop a user interface suitable for such users. In this paper we presented the design process we applied in order to develop a mobile application oriented to people living in Sri Lanka. During the design process we took in account several factors such as users level of literacy, familiarity in using the device, users cultural background, language beliefs. Starting from some scenarios based on our studies we have been able to carry out a list of non-functional requirements. They are aimed to develop usable interfaces for people

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