Rapid Application Development to Create Proof-of-Concept
Software Applications
Margarida Lucas da Silva
, Hugo Silva
and Daniel Gonc¸alves
Instituto Superior T
ecnico, Av. Rovisco Pais, 1, 1049-001, Lisboa, Portugal
INESC-ID, Rua Alves Redol, 9, 1000-029 Lisboa, Portugal
Instituto de Telecomunicac¸
oes, Instituto Superior T
Av. Rovisco Pais, 1, Torre Norte - Piso 10, 1049-001, Lisboa, Portugal
Rapid Application Development, Rapid Application Customization, Autism Spectrum Disorders.
Rapid application development is the best way to test prototypes by giving a solid performance for user’s
tests, while rapid application customization it is the best approach to easily test the user’s needs, such as
children with autism spectrum disorders. In this paper we present a framework of a platform designed with
these concepts in mind. This platform is a standalone multimedia and rich content software, targeted at stu-
dents with special needs, that allows to easily expand the functionalities and create proof-of-concept software
Software has evolved giving several potential solu-
tions for our everyday problems, but still can be diffi-
cult to reuse a good tool and adapt it to a specific need,
since the target is typically the general population.
This brings a need to have access to a tool that allows
to easily develop diferent functionalities and adapt the
tool, with end-users in mind. my.Troc@s.net comes
as a answer to create fast prototypes and easily create
a specific tailored tool. The constant evolution in ICT
brought a wide range of new possibilities to help peo-
ple with learning disabilities access new opportuni-
ties for learning, entertainment and personal develop-
ment. Children with ASD are included in this group,
and although many approaches have been tested, few
have been adopted or successfully integrated in the
daily life of the children, their tutors or caregivers
(Putnam and Chong, 2008). Also, it is difficult for
tutors to easily adapt the tool for each child, which
makes the need to create a tool with two end users.
It is still difficult for tutors to become autonomous in
the process of managing and adapting the available
tools to the needs of children with ASD; we haven’t
found usability studies specifically focused on this as-
pect but the tools that we have reviewed to date gen-
erally require a backend for content management, and
as such, the process is not as easy as it could be. Web
technologies and related standards have provided sev-
eral well-supported means, which can be easily mas-
tered by a broad audience; these technologies can be
extended to Augmentative and Alternative Commu-
nication (AAC) software development, promoting the
involvement of the “user in the loop” due to the sim-
plicity they provide. In this paper we describe a stan-
dalone software application for promotion and train-
ing of social communication skills in children with
ASD. It is based on a framework for rapid applica-
tion development (RAD), and rapid application cus-
tomization (RAC). The underlying framework can be
generalized for the development of software targeted
at people with special needs; the main design princi-
ple for this approach was to enable tutors and profes-
sionals in the field to fully manipulate the overall con-
tents and look-and-feel autonomously with little train-
ing or support. We will describe an application called
myTroc@s.net, that takes advantage of the framework
presented, but other examples of applications are also
available at (Lourenc¸o et al., 2013). Some experi-
mental results with the platform are available in (Lu-
cas da Silva et al., 2011). This paper is organized
as follows: Section 3 goes through the main func-
tionalities of Troc@s; Section 4 explains the concept
of profiles as a way of achieving the rapid applica-
tion customization for tutors; Section 5 describes the
RAD/RAC framework depicting how we achieve the
desired flexibility and adaptability; and finally, Sec-
tion 5 summarizes the main results and conclusions.
Lucas da Silva M., Silva H. and Gonçalves D..
Rapid Application Development to Create Proof-of-Concept Software Applications.
DOI: 10.5220/0004698202990306
In Proceedings of the International Conference on Physiological Computing Systems (PhyCS-2014), pages 299-306
ISBN: 978-989-758-006-2
2014 SCITEPRESS (Science and Technology Publications, Lda.)
In the last decades, a number of software applications
have been developed for people with special needs,
mostly targeting computer-based learning. These
however, have been developed in a more enabling
and functional perspective centered in the individual
himself (Emiliani et al., 2009) (Helal et al., 2008)
Specifically designed for children with ASD there is
the Zac Browser
, which allows autonomous usage
of the Internet, together with other tools as activi-
ties, games, and videos. This platform is especially
designed for recreational and entertainement use, as
such, it does not explore the interpersonal communi-
cation specificities. Furthermore, tutors are limited
at a content manipulation and tool adaptation levels.
is a suite of applications that enables the
adaptation of learning materials to the needs of each
child. The program has a large database of symbols
they call Picture Communication Symbols (PCS)
and allows the users to create any kind of customized
material, such as schedules, manual communication
boards, books, teaching materials, etc. The mate-
rial can be used in the computer or printed, making
this tool usefull to create materials for teaching, how-
ever, this software is designed for the tutor and was
not conceived to be used by children. TeachTown
is a Computer-Assisted Instructional (CAI) program
designed for developmental ages between 2-6 years,
specifically to meet needs of ASD population. The
program includes a comprehensive curriculum that
aligns to standardized measures, which integrated the
following learning domains: 1) Language Develop-
ment; 2) Social and Emotional Skills; 3) Adaptive
Skills; 4) Cognitive Skills; 5) Language Arts; and 6)
Mathematics. The curriculumdepends on the perfor-
mance and is adjusted for each student. Tutors can
customize the curriculum to meet Individual Educa-
tional Plan (IEP) goals. TeachTown also collects data
from the children usage and produces reports, to track
the student progress. This tool is one of the most com-
plete applications for children with ASD currently
available, and extensive research has proven that an
ICT tool like TeachTown has beneficial results. How-
ever, this tool is not completely customizable, and it is
not targetting all the children preferences, which can
have poor effects in their attention and engagement.
Furthermore, this tool was devised for individual use,
and lacks features that can promote communication
and social interaction skills. Although not specifically
designed for children with ASD, another tool of pos-
sible application is the Grid 2
. This is a customizable
solution that replaces the conventional keyboard and
mouse by a pointing device applied in a virtual key-
board, through which it is possible to use any software
on the computer. However, this is a platform aimed
to a different target population, with special needs in
terms of accessibility.
my.Troc@s.net was designed with the purpose of
encouraging socialization, facilitating interaction
among children with ASD, and also allowing tutors
to easily customize the contents and overall look-and-
feel of the platform.
The application can be fully customized with
icons, background images and the contents that allow
each child to be more effective while using it. Chil-
dren can even use their own drawings or favourite im-
ages in a semiotics approach to better associate each
feature of the software with the underlying function.
Tutors have full control over the software and they
can intervene at virtually all levels. They can act at
the content level, where contents are structured and
organized under the application folder tree, just as
any other document is organized in regular computer
work. But they can also act all the way up to the pre-
sentation level, where with basic training they are able
to manage the screen and navigation structure by sim-
ply editing the HTML files.
All the activities are targeted at communication
skills training. They are based on multimedia con-
tent: images, videos, audio, and stories that children
can autonomously browse through and learn from. In
addition there is also a message board, and content
preference sharing options, these being the main con-
tribution of the platform to the field, when compared
to existing work.
In the message board children can post messages
to their colleagues. The sender child has a buddy
list with names and photos of all counterparts, from
which the receiver colleague can be chosen. The mes-
sage can then be written either through text, picture
exchange (Bondy and Frost, 2001), or a combination
of both methods. When the receiver colleague opens
the message board, he will immediately be able to see
all of the messages sent to him by others. Figure 1
shows the message board screen.
For content preference sharing, associated to each
multimedia item (image, sound or video), there is a
positive and a negative preference option. These al-
Figure 1: Message history screen of myTroc@s.net.
Figure 2: Image detail with the content preference sharing
low the child to express and share with its counter-
parts at any time, his/her preference regarding a given
individual element. This information is associated
with the content and shown every time it is accessed,
allowing all children to see the opinion of their col-
leagues. Figure 2 illustrates one of the tasks of the
platform, with the content preference sharing pane on
the right side of the screen.
As a way to empower the tutors we created a possi-
bility of having user-tuned content as a way of further
exploring the individual differences of children with
ASD. This problem is not exploited enough in order
to improve the children engagment while using soft-
ware that can be beneficial for them. In this section
we will detail our proposed methodology to the prob-
lem of profile management.
4.1 Concept
The profile concept arises from the need, shown by tu-
tors to create customized layouts and content for the
children. As in content management, we needed the
process to be straightforward and familiar to the tutor,
and to create a mechanism that allowed them to eas-
ily customize the whole platform, taking into account
different user profiles. We decided to support this fea-
ture also on a folder structure of the Operating System
(OS), since it was a fast and easy way to handle large
amounts of files in bulk, and also because it involves
procedures that the tutor are familiarized with. Using
the “My Documents” metaphor available in all Oper-
ating Systems, we created profiles as if they were the
“My Documents” of each user. This allows tutors to
manage all the files individually, or to create shared
profiles, without having a limited number of profiles
per user. This method is usually familiar to all tutors
and simplifies the process of managing content when
compared to the typical backoffice or in-program set-
tings management approaches.
By creating profiles, the platform can be fully cus-
tomized to a user with icons, background images and
the contents that allow each child to be more effective
while using it. Children can even use their own draw-
ings or favorite images to better associate and man-
age the semiotics of each feature of the software with
the underlying function. With myTroc@s.net children
can have their own individual profile on the platform,
and visualize the application in the most engaging
way for them.
Tutors can act at the content level, where con-
tents are structured and organized under the applica-
tion folder tree, just as any other document is orga-
nized in regular computer work, as we can see in Fig-
ure 3(a). But they can also act all the way up to the
presentation level, where with the right training and
proficiency they are able to manage the screen layout
and navigation structure by simply editing the HTML
files (Figure 3(b)). The previous customization ap-
proach provided by Troc@s was still preserved; if the
tutor chooses to do so, he can use the base profile pro-
vided by the myTroc@s.net framework, and simply
customize the platform in a one-size-fits-all approach
where all of the children access the same customiza-
tion settings.
The application reads all folders and file names,
and uses them as content titles. This way, the ap-
plication is not bound to a main language, by using
everything that is specified by the tutor in the folder
and filenames. The activities presented to the child
in the platform are determined by the subfolders in
the profile folders assigned to each child, so if for
example the pictures folder didn’t exist in the profile
folder, then it wouldn’t be available as an activity in
myTroc@s.net. Also, the base profile is available as
default for all children.
The tutor can create as many profile as he/she
(a) myTroc@s.net con-
tent folder tree for a
given profile.
(b) A few of the
system files used by
Figure 3: FMS-based profiles, content and layout organiza-
Figure 4: Example of the profiles structure in
want’s, and assign them to any user; in turn, each user
can have an unlimited number of profiles, which al-
lows a better organization of contents. For example if
the tutor wants to share a class trip pictures, but not
all children in the school went to that trip, he can cre-
ate a profile for the class trip group, make the pictures
available there, and only the corresponding children
will have access to those pictures.
4.2 Management
Profiles can be used individually, or shared with any
number of users; for example, if the tutor has children
from different age groups that can share a few of the
activities (e.g. apps), he can create a common profile
for each age group and selectively assign it to each
child. When adding a profile to a child, the platform
gives priority to the leftmost profile specified, and so
on. This means that the content listed in the first pro-
file specified, will be the first to appear in the content
list view.
Profiles are specified in the a settings.json file
that is associated with each user, and where the tu-
tor only has to write the profile name with quotes,
separating profiles with a comma, for example: ”pro-
file”:[”profile02”, ”profile01”]. In this example, the
application first lists the profile02 content, then the
profile01 content, and finally, all content in the base
profile, which as the default profile, does not need to
be specified in the profile lists, and is automatically
available for all users.
In Figure 4 we can see an example on how the
profiles are applied; the base profile is available for
all children, and profiles profile01 and profile02 are
only individually and selectively assigned to a few
children. In each profile it is possible to override the
content folders that one wants to customize; in pro-
file01 images, videos and music are being customized,
while in profile02 only images and messages are be-
ing customized. In each folder the tutor can change
the menu icon, the background image, or the content;
to do so, he/she just needs to copy and paste any im-
age on the corresponding folder and rename it:
For the menu icon, the image must have the same
name as the folder. For example, the folder is
called images, then the icon must be called im-
ages. The file extension can be of any image kind
(e.g. jpg, png, bmp);
For the background image, the image must have
the same name as the folderwith the -bg suffix.
For example, if the folder is called images, then
the background image must be called images-bg,
and again the file extension can be of any file im-
We can see examples of this structure in Fig-
ure 3(b). We also have a gui folder, where the user can
change the like and no like icons (shown in the pref-
erences sharing pane), the main icon (that the child
uses to return to the main activity selection screen),
the out icon (that the child uses to close the platform),
and the HTML and CSS of the presentation layer, in
case the tutors learn how to adjust with it. All con-
tent available in a a given user profile will only the
accessible to the user(s) that have that corresponding
profile assigned. Using profiles allows the children
to have myTroc@s.net completely prepared for them,
following their preferences. Figure 5 illustrates a cus-
tomization of myTroc@s.net with two different pro-
(a) Profile customized for user A.
(b) Profile customized for user B.
Figure 5: Example of content customization in
The framework was designed with both the end-users
and the people behind application management in
mind, targeting the seamless delivery of rich multi-
media content, while providing high customization
levels, easy content management and maintenance by
non-technologically proficient individuals. Figure 6
presents an overview of the framework, which will
describe throughout the following sections.
5.1 File Management and Data
In myTroc@s.net we used a Model-View-Controller
(MVC) development approach; we implemented a
Python Websocket (Wang et al., 2013) (Flanagan,
2011) server, which takes advantage of the advanced
connectivity capabilities introduced by HTML5. In
this approach, we use the browser just as a front end
for content presentation and user interface, and all of
the automation, OS-level operations, and computing
tasks are supported by the Python programming lan-
guage and framework. We chose the use of Web-
Web Browser
Web Socket
Couch DB
Figure 6: Framework of the myTroc@s.net.
Sockets since they are a very straightforward way
of interfacing the browser with the “outside world”,
and because it has the advantage of providing a full-
duplex communication channel that can be used for
asynchronous interaction between the browser and
Python (in our case). Through this infrastructure, the
presentation layer implemented at the browser level,
sends requests to the Python back-end using a Mes-
sage Passing Protocol (MPP), for Python to manipu-
late the file system, read all files from the platform,
automatically generate thumbnails, among other op-
For data persistency we used the Couch DB
database engine, which is also managed by our
Python back-end. We selected Couch DB due to the
fact that it is a full featured database management
system, with the advantage of being document ori-
ented and natively structured in JavaScript Object No-
tation (JSON); as previously described, JSON is di-
rectly supported by JavaScript, providing a stream-
lined way of storing information produced at the pre-
sentation layer in the database and vice versa. All
preferences (like/dislike) assigned to the content and
messages sent by the child are saved in the database as
a JSON string associated to each user. myTroc@s.net
also saves logs with the user navigation, files loaded,
messages sent/received, likes, and amount of time
spent in the platform. All events that occur in the plat-
form are monitored by RPyC - Remote Python Call
which listens for all user interaction events, triggers
the corresponding actions (e.g. new message warning
or new file detection) and saves the event description
in logs.
5.2 Networking
Another feature incorporated in myTroc@s.net is the
support for networked and parallel operation, which
enables the automated synchronization of files across
computers, and also the simultaneous and near real-
time message exchange between children as any other
chat client (unlike the monolithic message board ap-
proach followed in Troc@s). This gives enables the
child to access his/her customized content from every
networked computer, and also to communicate with
other children and tutors using the myTroc@s.net
platform in other parts of the school or even in other
schools, since the platform synchronizes content and
messages across the network, allowing children to
commute and communicate with others outside of the
physical space of the school. To support this feature in
our platform we recurred to the Unison File Synchro-
, allowing the tutor to populate myTroc@s.net
in his personal computer and automatically propa-
gate the changes to the individual computers of each
child in a Dropbox
-like fashion. This functionality
was merely instrumental for the purpose of our study,
since it makes the customization process more conve-
nient for the tutors, however, it also sets an important
background for the real-world deployment of the out-
comes of our work as well as for future work to be
5.3 Attention Detection
To detect the user attention while using
myTroc@s.net, which will be used to evaluate
the child’s engagement in the platform, we used
the Python OpenCV wrapper
. For this feature
the myTroc@s.net framework uses the computer’s
camera, together with a Haar Feature-based Cascade
Classifier for Object Detection for automated detec-
tion of the face of the child. Using the frontal and
profile face cascades, if the child is not in front of the
computer, or not looking at the screen, the platform
detects it, and records the distraction state in the log
file; on the other hand, when the child returns to the
computer or looks again at the screen, the attention
state is detected and recorded in the log file. Figure 7
illustrates the attention and distraction cases.
For the tests, a log system was implemented in
the myTroc@s.net platform, which saved the cur-
rent user, together with the timestamps in which
we looked at the screen, and in which he looked
away. Taking into account a physiological head
movement frequency limit of 0.5Hz (Calais-Germain,
2007; Berthoz et al., 1992), the OpenCV was setup to
only check for the head position every 2 seconds.
http://www.cis.upenn.edu/ bcpierce/unison
(a) The child is in front
of the computer and
looking at the screen.
(b) The child is in front
of the computer but
is not looking at the
Figure 7: Attention detection while using the
myTroc@s.net platform.
5.4 Logs
In order to record the actions and interaction patterns
of children while using the myTroc@s.net platform,
our framework was fitted with a logging mechanism
which enables us to derive objective measurements
that can be used to characterize the experience of the
child when using the platform. For each user, a new
log file is created every time he logs in, and the cur-
rent date and time is assigned as the file name. The
framework produces 6 different types of logs through
which we can audit the child’s behavior; per user ses-
sion it records:
1. Apps: Saves the date and time in which an exter-
nal app was launched, and saves the full path of
the loaded applications.
2. Face Detection: Each line has two columns, and
represents a change in interaction status from at-
tentive to distracted and vice-versa, the timestamp
has the time in seconds since the Epoch and is
saved on the left column, while on the right col-
umn, a Boolean value is stored, where 0 is the
state in which the child looks away, and the 1
is the state in which the child looks back at the
screen (attentive).
3. Likes: Saves the date and time of every
like/dislike selection that the child made using
the preference sharing pane presented along with
each content item, and lists the full path of the
chosen content item together with the type of se-
lection (whether it was a like or dislike).
4. Activities: Saves the date and time in which a
given activity was loaded, with the indication of
the type of activity that was loaded and what sec-
tion did the child visit during the session.
5. Interaction: Saves the date and time of nearly
all human-computer interaction events generated
by the child through the peripherals, namely the
mouse events (move up, down, click, double click,
and scroll events, the x and y coordinates of the
pointer, and the left, right or middle button clicks),
and the keyboard events (key up, down, and press,
as well as the character code).
6. Messages: Saves the date and time in which the
message was sent, together with the indication of
the recipient peer, the number of characters in the
message, and the number of pictures included in
the message.
These logs are created to record every activity of
the child while using the the platform, and will be
used in our study to quantify the children’s commu-
nicative and behavioral patterns. Preference sharing
and Messages are social interaction activities, directly
related with the communication skills, and as such
it is important to track this activity individually, and
measure it, to see how it evolves over time, as well as,
and compare it to other children.
The Apps show us the type of application that chil-
dren are using, which helpful to give some insight
about their preferences and capacities. In our study,
Apps are particularly related with story telling activi-
ties that the tutors configure in the platform, in partic-
ular with the Microsoft PhotoStory and with the Digi-
tal Library from the National Reading Plan
; both are
directly related with communicative interaction pat-
terns developed by the children.
Activities notes all activity of a child in the plat-
form, which can be helpful to understand the children
behaviour and focus of attention while using the plat-
form (e.g. if the child spends some time watching
photos, or videos and no time listening to music). In-
teraction is a log that allows us to get more detail
about the behavior of the children in each activity (e.g.
see if the child was doing anything during that period
of time, or analyze how he/she navigates in the con-
The Face Detection log enables us to determine if
the child was looking at the computer screen or not,
thus providing further behavioral information which
would not be accessible otherwise. This enables us
to draw some conclusions about their attention levels
while using the platform.
Combining all information available in the logs,
we can have an objective and quantitative perception
of the child’s behaviour and perform group analysis
in order to determine the effect of user-tuned content
in the educational strategies and outcomes of children
with ASD.
In this paper we present a novel methodology
materialized by a platform and framework called
myTroc@s.net, which emerged from the real-world
needs of special education teachers. Our approach is
focused on customization as a way of potentiating the
capabilities of each child and improve their overall
outcomes, by introducing the concept of profiles as a
way of enabling the full customization of the platform
for each child, together with a RAD/RAC framework
designed to streamline the customization process for
the tutors. Besides the children, we also focused our
attention on the caregivers, since they are the ones that
interact directly with the children, and prepare the in-
dividual profiles for the children.
The biggest novelty in this approach is the way we
take advantage of several tools and known metaphors,
and model their purpose, to create a rapid application
that can fully answer two user types needs. In this
case this simple application can be a simple content
management for large amounts of files with a small
learning curve, and also a learning tool for the chil-
These goals helped us shape the application and
create a framework that can easily aggregate more
functionalities, and deliver a simple application using
web technologies that allow an easy full manipula-
tion. myTroc@s.net is an example of an application
that could be easily created using the framework pre-
sented, by taking advantage of web technologies and
the folder system to easily format an application, ease
to use by all end users.
Our future work first will focus on improving
the current application, so we can further improve
the user experience. To help the tutors with con-
tent customization, it would be convenient to have
the possibility of embedding YouTube videos in
myTroc@s.net; most tutors said that if they had this
functionality, they would have further customized the
videos activity, since YouTube allows them to eas-
ily search and visualize video content. Still concern-
ing the content customization, this process could be
improved by creating a drag and drop page feature
to manage files and folders across profiles through
the myTroc@s.net interface, or by providing feedback
about the effect that the changes to the File Manage-
ment System (FMS) have on the profile configuration.
In order to allow a more sustainable and contin-
ued engagement between the users and the platform,
and also to bring together parents and children dur-
ing the time they are away from each other (e.g. at
school), one next step will be to create a mobile ver-
sion of the platform, to be used in smartphones and
tablet devices, enabling parents and tutors to interact
with the children anywhere (and vice-versa).
Besides, given the natural curiosity of the child
toward the touch-based interfaces, mobile devices can
also facilitate the interaction between the child and
the platform, further enhancing the motivation of the
child towards its use. Due to our web-based software
architecture, most of the platform can actually already
be used in mobile devices, provided that the Python
websocket server and Couch DB database are hosted
in a remote server.
To facilitate the interaction between the child and
the Troc@s-enabled devices, we are now preparing
the framework to respond to physical objects. With
this feature, children will be able to use their toys
and other objects with which they are familiar with,
to control and navigate in the platform. By introduc-
ing wireless RFID tags in each object, a reader in the
computer will be able to detect a given object that the
child is holding nearby, and change the behavior of
the platform accordingly, enabling an easier naviga-
tion and increased interactivity.
This work has been partially funded by Fundac¸
Portugal Telecom, ASUS Portugal, and by the
ao para a Ci
encia e Tecnologia (FCT) under
the grant SFRH/BD/65248/2009 and project PEst-
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