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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Study on the Use of Gameful Approaches in Self-paced "learn to code" (SPL2C) Apps</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Joan Arnedo-Moreno</string-name>
          <email>jarnedo@uoc.edu</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Susanna Tesconi</string-name>
          <email>stesconi@uoc.edu</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Maria Jesús Marco</string-name>
          <email>mmarcog@uoc.edu</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>David García</string-name>
          <email>dgarciaso@uoc.edu</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marta Fondo</string-name>
          <email>mfondo@uoc.edu</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Author Keywords</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Programming; Coding skill; Education; Mobile app;</institution>
          ,
          <addr-line>Gamification; Gamful element; Testing</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>eLearn Center, Universitat Oberta de</institution>
          ,
          <addr-line>Catalunya</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Coding skills have gained popularity beyond the technical programs of university education, leading to the emergence of many free online resources for informal learning. Among them, self-paced "learn to code" (SPL2C) apps are very popular in digital distribution stores. However, the academic literature agrees that acquiring coding skills is a demanding endeavour, with one of the highest dropout rates among all fields in Computer Science. For that reason, such apps are very sensitive to user retention, which they often address by including game-like design principles or elements that nicely mesh with their sandbox "study at your own pace" nature. The present paper studies this category of apps in order to identify the most relevant ones at this moment, while analyzing which are the most popular game elements used in them. This makes it possible to compare the gameful design approaches in this kind of apps with others in the wider educational context.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>CCS Concepts</title>
      <p>•Human-centered computing ! Human computer
interaction (HCI); •Applied computing ! Computer-assisted
instruction; •Social and professional topics ! Adult
education;</p>
      <p>
        The increased interest in acquiring coding skills has lead to
the appearance of a large number of compelling informal
resources. Directed at kids, there are LOGO-like games, such as
Coddy [
        <xref ref-type="bibr" rid="ref17">18</xref>
        ], among many examples, or creative development
environments, the main example being Scratch [
        <xref ref-type="bibr" rid="ref10">11</xref>
        ]. For an
older audience, specialized question and answer sites, such
as Stack Overflow [
        <xref ref-type="bibr" rid="ref7">8</xref>
        ], and mobile SPL2C apps are especially
popular. However, the crux of the matter is that learning to
program is difficult, and even in formal studies, programming
courses tend to have very high dropout rates. Several theories
have been formulated in the educational literature on the topic
to find the reasons [
        <xref ref-type="bibr" rid="ref13 ref18">14, 19</xref>
        ]. Student motivation and dedication
is a key factor, as becoming an expert programmer may take
up to 10 years [
        <xref ref-type="bibr" rid="ref22">23</xref>
        ].
      </p>
      <p>
        Focusing on this last group of mobile apps, their approach to
cope with users’ motivation and retention problem is to offer
a more flexible and engaging experience in comparison to
traditional courses. Usually, as their core approach, they offer
a sandbox environment, structuring knowledge into small bits
that can be consumed step-by-step, with a very clear learning
path that allows students to slowly advance at their own pace,
without the constraints of rigorous study terms. Often, this
scaffolded learning approach is complemented with the use
of game-like design principles or elements (without
becoming full fledged games themselves) [
        <xref ref-type="bibr" rid="ref14">15</xref>
        ], such as challenges,
concrete goals or extrinsic incentives [
        <xref ref-type="bibr" rid="ref23">24</xref>
        ]. As a result, users
often report that they prefer these approaches when learning
to code [1], thus providing a reason for its popularity.
This paper focuses on these so called SPL2C apps, not targeted
to children, which can be found in numbers in mobile digital
stores. The goal is to identify the most relevant apps to learn
how to code that include gameful approaches to engage users,
but are not games themselves. Then, to provide a thorough
analysis on the most popular game elements in these apps,
and to compare them to other such approaches in the general
educational context. This study provides an insight on this
mobile app segment and the particularities of their chosen
gameful approaches in the specific context of the informal
acquisition of programming skills.
      </p>
      <p>The papers is structured as follows. First of all, a brief
background on the study of gameful approaches in the context of
learning is laid out in Section 2. Following, Section 3 presents
the methods of research, how the data was compiled and the
main body of the analysis of the selected apps. Section 4
provides reflection on on the results and how they relate to other
works on gameful approaches and learning. Finally, Section 5
concludes this paper and outlines further work.</p>
    </sec>
    <sec id="sec-2">
      <title>2. BACKGROUND AND RELATED RESEARCH</title>
      <p>
        The applications of gameful approaches in the context of
education at large have been extensively studied in several
literature reviews or surveys, all of them published after the term
"gamification" had reached the peak of Gartner’s Hype Cycle
for Emerging Technologies [
        <xref ref-type="bibr" rid="ref8">9</xref>
        ]. These reviews are very useful
to assess which dimensions are worth to consider when
analyzing this kind of proposals and, in particular, how to categorize
and compare their gameful elements.
      </p>
      <p>
        Some of such reviews focus on aggregating large amounts
of demographic data, such as the ones by Caponetto [
        <xref ref-type="bibr" rid="ref1">2</xref>
        ] and
Martí-Parreño [
        <xref ref-type="bibr" rid="ref12">13</xref>
        ]. The former study encompasses 119
papers from 2011 to early 2014, providing information about
year of publication, country and target population. The latter
considers 139 different papers on the topic, from 2010 to 2014
and the main aspects taken into consideration in the
categorization process are publication journal, institution of origin
and authors. There is also a brief survey on content constructs
(e.g. Effectiveness, Attitudes, Engagement, Cognitive, etc.),
but it is not based on an analysis of the proposals themselves
or their game elements, but through word frequency analysis.
In addition, a much smaller study, 26 papers from 2011 to
2013, can be found by De Sousa’s [
        <xref ref-type="bibr" rid="ref2">3</xref>
        ]. This one goes a bit
beyond simple data aggregation, presenting also a categorization
by research objective and enumerating all the studied papers.
Nevertheless, even though these surveys gather data from a
large number of publications and provide a good overall idea
of the context in which gamification is used in education, they
do not provide insightful information about how gamification
is implemented and which game elements are the most popular
and/or effective.
2012 to 2013 and mainly focuses on analyzing publications
according to game design elements (classified into Points,
Levels/Stages, Badges, Prizes/Rewards, Progress bar, Storyline
and Feedback), as well as expected outcomes. Dichev and
Dicheva also presented a quite thorough survey in 2017 [
        <xref ref-type="bibr" rid="ref3">4</xref>
        ], the
final result of successive incremental surveys also published
the previous years (nevertheless, data is only up to year 2015).
It includes 51 papers, categorized according to many different
dimensions, such as subject of study, type of learning activity
or learning and behavioral outcomes. The many game design
elements are identified by the authors to categorize works, but
a heavy emphasis is put on Points, Badges, Levels,
Leaderboards and Progress bars. Additionally, each included paper is
also individually categorized based on its Gamified elements,
Subject, Sample size, Duration, Data Collection and Outcome.
Both reviews reference every individual paper included in the
study and how each one can be traced to each chosen category.
Therefore, they provide the reader with a good starting point
for further analysis of the articles included in the reviews.
The latest review found at the time of this writing is from
Koivisto, published in 2018 [
        <xref ref-type="bibr" rid="ref9">10</xref>
        ]. This is the biggest study
that considers a categorization by game elements (although
the term "affordances" is used in this paper instead), including
128 papers up to 06/2015. Game elements are split into 32
different categories divided between Achievement/Progression,
Social, Immersion, Non-digital or Miscellaneous.
Psychological and behavioral outcomes are also taken into consideration.
However, probably because of the high number of papers, the
results are aggregated and papers are not referenced. Hence,
the study presents a good general overview of the most popular
game elements found in the literature but cannot be used to
further explore the topic, as it does not provides references to
the subjects of the study.
      </p>
      <p>
        Focusing on gameful approaches in the specific subject of
learning programming, a survey was published in 2017 [
        <xref ref-type="bibr" rid="ref4">5</xref>
        ].
However, it only includes 7 papers published from 2012 to
2014, and only 4 of them are actually about coding (the other
three are about related topics such as Software engineering
or databases). The range of gameful elements taken into
consideration for the analysis is also very limited, as it is only
centered on the well-known PBL template, based on Points,
Badges and Leaderboards. As a result, the utility of this study
is extremely marginal.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. RESEARCH METHOD</title>
      <p>The purpose of this study was to find out which kind of
gameful approaches are the most popular in "learn to code" mobile
apps. On that regard, it is worth noting that all of the previous
literature reviews (see Section 2) studied published papers, but
did not directly evaluate technological platforms per se.The
data gathering procedure followed a systematic process
devised to identify as many apps as possible that could then
become candidates for a more in-depth personalized study of
their characteristics.</p>
      <p>
        There are some literature reviews that do categorize papers by
game elements. The one by Nah [
        <xref ref-type="bibr" rid="ref15">16</xref>
        ] includes 15 papers from
      </p>
    </sec>
    <sec id="sec-4">
      <title>3.1 Research Questions</title>
      <p>The research questions for this study were:
RQ1 - How common is the use of gameful approaches among
the most relevant SPL2C apps?
terms used and the inclusion of other more generic keywords,
C language apps were sufficiently included nevertheless.
RQ2a - What are the most common gameful elements in
SPL2C apps?
RQ2b - Are the gameful approaches in this context different
from the ones found in education at large?
RQ3 - How are the gameful elements implemented and which
are the idiosyncrasies of the "app" context?</p>
    </sec>
    <sec id="sec-5">
      <title>3.2 Identification of candidate apps</title>
      <p>Candidate apps were selected through a multi-step process
that relied mostly on the Google Play Store. The Play Store
was chosen given Android’s mobile market share (about 75%),
and its simplicity in the app publication process, which makes
it a popular default choice for developers. Its public API also
allows the automation of some tasks, opening the possibility
to create an initial very large pool of apps and process their
meta-data, something that would be extremely time consuming
using a fully manual approach.</p>
      <p>
        Step 1) A very broad search was executed on Google’s Play
Store [
        <xref ref-type="bibr" rid="ref6">7</xref>
        ]. An automated process was developed to perform
a batch of queries according to different keywords, taking
advantage of the store’s API. The following Context-Free
Grammar (CFG) defines the universe of queries (QUERY)
used.
&lt;A&gt; --&gt; learn | practice
&lt;B&gt; --&gt; to code | to program
&lt;C&gt; --&gt; coding | programming
&lt;L&gt; --&gt; (list of programming language names)
&lt;P&gt; --&gt; &lt;L&gt; | &lt;C&gt; | &lt;B&gt; | &lt;L&gt;&lt;C&gt;
&lt;QUERY&gt; --&gt; &lt;A&gt;&lt;P&gt; | &lt;L&gt;&lt;C&gt; | &lt;C&gt;
The list of programming language names to be used in this
study was extracted from the most popular ones according to
Stack Overflow’s 2019 survey "Most Popular Technologies
- Programming, Scripting, and Markup Languages"1. Stack
Overflow is one of the most renowned question and answer
sites for professional and enthusiast programmers on the
Internet (usually ranked among the top 50 in the Global Alexa
ratings2), and about 90.000 people participated in the survey.
However, when configuring the list, it was found that the
"C" language name, lacking expressivity by being a single
letter, and other relatives such as C++ or C#, having special
characters, caused queries to behave erratically in the Play
Store. Therefore, they were not included. At the end, the list
was composed by 13 of the 16 most popular programming
languages, the excluded 3 being those from the C language
family.
      </p>
      <p>Using this approach, a total of 114 different queries were
executed, obtaining a total of 2214 individual results. Once
repetitions across separate queries were taken into account
(612), the number of starting app candidates was set at 1602.
A preliminary inspection showed that, given the broad search</p>
      <sec id="sec-5-1">
        <title>1https://insights.stackoverflow.com/survey/2019 2https://www.alexa.com/topsites</title>
        <p>Step 2) The list of candidates was pruned according to the
following set of strict and basic criteria which would ensure
some degree of popularity and relevance of the chosen apps.
It should be taken into account that the uncurated nature of the
Play Store allows anybody to publish an app, regardless of its
quality or following. Many apps are hardly ever known by the
public, or downloaded by very few people. The criteria used
to prune the list of candidates from Step 1 were:</p>
      </sec>
      <sec id="sec-5-2">
        <title>a) Market status as "Published" (i.e. an active app).</title>
      </sec>
      <sec id="sec-5-3">
        <title>b) Category set as "Education".</title>
      </sec>
      <sec id="sec-5-4">
        <title>c) A rating of at least 4.0 (i.e. 4 stars out of 5).</title>
      </sec>
      <sec id="sec-5-5">
        <title>d) Minimum number of times rated, 1.000.</title>
      </sec>
      <sec id="sec-5-6">
        <title>e) Minimum number of downloads, 10.000.</title>
        <p>To provide some perspective, a very popular learning app
such as Duolingo, ranked 100 in the Play Store at the time of
this writing, has been rated 7.327.126 times at 4,7 stars, and
downloaded more that 100 million times.</p>
        <p>Again, this was a fully automated process, from the app
metadata also obtained during Step 1. The chosen values were
finetuned several times until an approachable number of results
was obtained. Under these final criteria, 594 apps did not
fulfill b), 763 did not fulfill c), 1552 did not fulfill d), and 1291
did not fulfill e), for a total of 1565 discarded apps. It must
be noted that many apps did not fulfill several criteria at once,
and all apps fulfilled criteria a). After the filtering process, the
number of app candidates was reduced to only 37.
Step 3) From this step on, the process moved from an
automated system to a manual one. The resulting apps were
installed on a Pixel Android phone. In order to identify whether
gameful approaches were used for user engagement, for each
app, its description was read, and then executed and manually
inspected. The main reasons for discarding apps during this
step follows, with the total number of discarded apps between
parentheses at the end:</p>
        <p>Directed at children or games. Not about professional
programming languages (2).</p>
      </sec>
      <sec id="sec-5-7">
        <title>No meaningful gameful approaches included (6).</title>
        <p>Actually, instances of the same app, each for a different
programming language (9).</p>
        <p>Programming tools, but not really learning apps. E.g. An
integrated Development Environment (IDE) or plain API
references (10).</p>
      </sec>
      <sec id="sec-5-8">
        <title>Not really about learning how to program at all (1).</title>
        <p>The final number of core candidate apps was thus reduced to
9.</p>
        <p>Step 4) As an additional step to fine tune the selection process,
the list of "similar apps" provided by the Play Store for each
of the 9 apps was then taken into consideration, searching for
additional suitable candidates, somehow missed during the
automated processes. During this step, interesting apps were
taken into consideration even when they did not strictly meet
all criteria applied during the automated process of Step 2
(mostly, minimum number of times rated). Four additional
apps were considered eligible, for a total of 13 final candidates.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>3.3 Analysis</title>
      <p>
        The final list of apps considered for study is shown in Table 1.
A summarized name, that is used in some parts of the rest of
this paper, is written in column "Short". Some general stats
such as store rating (Stars), number of times rated (Ratings)
and approximate minimum number of Downloads are also
included, to provide some insights about their popularity. It
should be noted that the Play Store does not provide an exact
number of downloads, just a minimum-maximum range. In
addition, a footnote with the exact package name has been
included in the table for those apps with a very generic name,
broadly repeated in the store, to better identify them.
The analysis was based on interaction with each application
as a standard user for one week. During this time, different
gameful elements were identified and classified accordingly.
Some possible categorizations were presented in Section 2.
However, the chosen approach was based on "The Periodic
Table of Gamification Elements" proposed by Marczewski in
his Gamification Hexad User Types framework, a widely
accepted and popular approach [
        <xref ref-type="bibr" rid="ref11">12</xref>
        ]. This table encompasses
52 different elements, divided in eight categories. Of these,
six are mapped to specific user preferences towards
different motivations in non-leisure contexts (also know as "user
types"), and the remaining two are considered generic across
all kinds of users, labelled as "General" (GEN) and "Reward
Schedule" (SCH). This framework was validated by Tondello
et al. [
        <xref ref-type="bibr" rid="ref19">20</xref>
        ], presenting a standard scale to score users’
preferences, and their findings demonstrating the usefulness of the
Hexad User Types model as a measure of preferred design
elements. The six user types, each providing an insight of the
kind of elements included, can be briefly described as follows:
      </p>
      <sec id="sec-6-1">
        <title>3tursky.jan.nauc.sa.html5 4ab.java.programming</title>
        <p>Socializers (SOC): Motivated by relatedness. They want to
interact with others and create social connections.
Free Spirits (FRS): Motivated by autonomy and
selfexpression. They want to create and explore.</p>
        <p>Achievers (ACH): Motivated by mastery. They are looking
to learn new things and improve themselves. They want
challenges to overcome.</p>
        <p>Philanthropists (PHI): Motivated by purpose and meaning.
They are altruistic, enjoying when giving to other people
and enriching the lives of others in some way with no
expectation of reward.</p>
        <p>Players (PLA): Motivated by rewards. They will do what is
needed to collect rewards from a system.</p>
        <p>Disruptors (DIS): Motivated by change. They want to
disrupt the system, either directly or through other users, to
force change that suits their interests.</p>
        <p>It must be noted that, even though the list is divided by user
type, in this study, the eight categories defined by Marczewski
are only used to better organize game elements. Studying
the relationship between the identified elements and user type
preferences was out of the scope of the study.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>4. RESULTS AND DISCUSSION</title>
      <p>The summary of the results provided by the in-depth analysis
is shown in Table 3, located in Appendix I because of its size.
Columns describe apps, listed using its summarized name (see
Section 3.2) and rows enumerate gameful approaches, using
Marczewski’s classification (see Section 3.3). Even though
Marczewski’s list includes up to 52 gamification elements,
only those that were actually identified in any app during the
analysis are listed, for a total of 25. Elements included in a
given app are marked as "Y", and those not included as "N" (i.e.
Yes/No). The end column shows how many times a particular
gameful element appeared across each of the different apps,
whereas the end row shows the total sum of game elements
included in each individual app.</p>
      <p>From the information in the last row of the summary table,
it is possible to provide an answer to research question RQ1,
"How common is the use of gameful approaches among the
most relevant "learn to code" apps?". The number of elements
included range between 2 and 18 (mean=7.615, std=4.61). In
5 out of all 13 studied apps the use of gamification is very
marginal. 2 elements only, in three of them: "Programming
Hub", "Master Android" and "Java Programming". In the rest,
the use of gameful approaches could be considered common
and consistent with the app itself. A special mention is worth
for "Programming Hero" and "SoloLearn", both at the top with
15 and 18 elements, respectively. Therefore, these two could
be considered the most relevant ones in the context of gameful
approaches in SPL2C apps.</p>
    </sec>
    <sec id="sec-8">
      <title>4.1 Comparison with other gameful approaches</title>
      <p>Regarding differences among gameful approaches in apps
and other educational contexts, the last column from Table 3
allows clearly answering research question RQ2a, "What are
the most common gameful elements in SPL2C apps?". The top
five most common gameful elements in this kind of apps are,
by order: "Progress/Feedback", "Points", "Badges", "Fixed
Rewards", and "Challenges". Its is noteworthy that in those
applications with a very limited number of gameful elements,
Points and Badges (both among the most common) are usually
the ones of choice. Also, since there are many instances of
different kinds of reward elements, Marczewski defines three
different subtypes (fixed, time-dependent and random), they
appear in 8 out of 13 different apps.</p>
      <p>In order to answer RQ2b, "Are the chosen approaches in this
context different from the ones found in education at large?",
the top five elements from each review that did perform a
categorization (see Section 2), are also listed in Table 2. For
a better comparison, the first column shows the results from
RQ2a, ordered by rank. On that regard, it is worth noting
that there is a difference between the concept of "Level" as
defined by Nah, and the rest of the literature (including this
paper). In the former, its meaning is equivalent to "Stage",
whereas in the rest of the publications it is used to define some
kind of character growth or power. Therefore, it has been
considered that Nah’s "Levels" are similar to Marczewski’s
"Challenges" or Koivisto’s "Quests". Also, Marczewski
considers "Progress/Feedback" as a single element, whereas other
studies often differentiate between "Feedback" and "Progress"
(usually just labelled as "Progress bars"). Therefore, for a fair
comparison, both kind of elements are aggregated in the final
results.</p>
      <p>From this ranking, it can be seen that elements such as "Points",
"Badges" And "Leaderboards" are very common and appear
in almost all of them, one might say unsurprisingly. This triad
of elements is very common in the literature, usually used
in conjunction and labelled as PBL (referring to the initials
of each element). However, it is an interesting finding that
"Leaderboards" are not actually that common in SPL2C apps
in particular (2 out of 13 apps use them). In addition, the top
element in this kind of apps is "Progress/Feedback", which
only tops the rankings, 5th position but very close to the 6th,
in Koivisto’s ssurvey. Therefore, two key differences have
been detected between approaches in education at large and
SPL2C apps.</p>
    </sec>
    <sec id="sec-9">
      <title>4.2 Relevant properties of chosen gameful elements</title>
      <p>Finally, the answer to research question RQ3, "How are this
gameful elements implemented and which are the
idiosyncrasies of the app context?", requires going beyond the
summarized data, and using a more qualitative approach, extracted
from the interaction with the apps as users during the analysis.
Answering this provides better insights on how game elements
work.</p>
      <p>As seen in the answer to RQ2b, some very common
gameful elements in education at large are also popular in SPL2C
apps, such as points, badges or level ups, and their
implementation is not too different. However, the top element
is "Progress/Feedback", usually implemented also in a very
straightforward manner with progress bars, showing how far
into a lesson or course the student has progressed. However,
sometimes the preferred metaphor is a semicircular gauge and
a percentage. There are also some more elaborate variations,
such as an adventure map that an avatar representing the
student traverses (Grasshopper, Programming Hero; see Figure
1a). On regards to the "feedback" part of this element, lesson
completion is often assigns stars or medals, in a similar manner
to levels in some videogames, depending on exercise accuracy
(Codemurai, Py, Programming Hero; ; see Figure 1a and 1b).
Only SoloLearn provides some extra aggregate feedback and
global student stats by given different categories, quite similar
to gamification player-types: learner, programmer, challenger,
influencer and collaborator (see Figure 1c).
The next kind of gameful element at the the top five in this
kind of apps are Reward related ones, almost always
implemented using a Fixed Schedule or Time Dependent strategy
(using Marczewski’s nomenclature). The former type is very
common, always taking the form of daily or weekly "streaks".
The app registers, and clearly shows, the number of
consecutive days a student has logged in and advanced in a lesson.
After some number of consecutive days, usually a week, the
student is rewarded, mostly, with some variation of points.
A few apps also use a Time Dependent strategy (DataCamp,
Codemurai, Mimo, SoloLearn), on top. In addition, points
are also automatically awarded every day the user logs in, or
there is a daily challenge (i.e. an exercise or test) that is only
available for 24 hours, mimicking the behaviour of many
Freeto-Play mobile games. In one case (Codemurai), this system
also incorporates a Consequence element when exercises are
failed, using a videogame-like "3 lives" mechanism, that goes
beyond simple scoring.</p>
      <p>It is also worth noting that, even though several different
gameful elements related to socialization (Marczewski’s Philatropist
or Socializer player types) have been identified, few apps take
them into consideration. They are seldom integrated in the
app itself, and mostly part of the dynamics of an external
discussion forum. The only exception is the Sharing
Knowledge element, based on the ability to publish coding personal
projects and process comments/voting mechanisms from other
users. In fact, SoloLearn is the only app that makes a relevant
use of this kind of elements, of special note being the ability
to duel with other students in a player-vs-player competition.
On regards to the rest of gameful elements, even though the
analysis shows a wide breadth of different ones, up to the
25 identified, their use is marginal (about half of them make
1-3 appearances at most). However, among them, the use of
narrative or themes in two apps, an often underused element,
deserve some attention. In Grasshopper, the student is guided
through the lessons by this animal, as a kind of pet and
companion during the coding exercises. In Programming Hero, the
student becomes an astronaut and uses the metaphor of space
travel through different planets (lessons) to advance through
the content (see Figure 1a). Therefore, the use of a metaphor
goes beyond the "Progress/Feedback" element, as previously
mentioned, and permeates the whole user experience.</p>
    </sec>
    <sec id="sec-10">
      <title>5. CONCLUSIONS</title>
      <p>This paper has analyzed the most relevant SPL2C apps in order
to assess their use of gameful approaches for user retention,
and how they are implemented. The goal was to compare
them to approaches in education at large, to try to find the
particularities of the mobile app educational context, if any.
Also, this study has shown that gameful approaches are also
used in this kind of apps, and in some cases make an extensive
use of them.</p>
      <p>From the answers to the proposed research questions, it is
shown that this kind of apps have their own idiosyncrasies.
Even though some very popular gameful elements in education
at large are included, such as points and badges, some others
are not, as is the case of leaderboards. Furthermore, they
especially emphasize elements related to progress/feedback,
which play a minor role in most proposals in the literature
related to gamification in education. Timed challenges are
also found to be quite relevant, but not usual in education at
large.</p>
      <p>Expected future work is twofold. On one hand, a more
usercentric analysis would be suitable, measuring up to which
degree the chosen gameful elements are actually engaging,
and taking into account player types (or any other approach
to categorize the different kinds of users). On the other hand,
and moving beyond the topic of gamification itself, the chosen
apps will be further analyzed in order to classify their preferred
educational resources and tools. This will allow to assess how
common these resources are in the educational literature and
their perceived usefulness in learning programming.</p>
    </sec>
    <sec id="sec-11">
      <title>6. ACKNOWLEDGEMENTS</title>
      <p>This work was partly funded by the eLearn Center (Universitat
Oberta de Catalunya) through the Xtrem Project programme.</p>
    </sec>
    <sec id="sec-12">
      <title>7. REFERENCES</title>
      <p>1. J. Boustedt, A. Eckerdal, and R. et al McCartney. 2011.</p>
      <p>Students’ Perceptions of the Differences Between Formal
and Informal Learning. In Proceedings of the Seventh
International Workshop on Computing Education
Research (ICER ’11). ACM, 61–68.</p>
    </sec>
    <sec id="sec-13">
      <title>APPENDIXI</title>
      <p>r
P
a N N N N N N N N N N Y N N Y N N N N N N N N N N N 2
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e N N N N Y N Y N N N Y N N Y Y N N N N Y N N Y N N 7
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rH N N N N Y N N N N N N N N N N Y N N N N N N N N N 2
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r N N N Y Y Y N Y N Y Y Y N Y Y Y Y Y N Y N N N Y Y 1
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n N Y Y N Y N N Y N N N N N N N N N Y N N N N N N N 5
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o N N N N Y Y N Y Y N Y N Y Y Y N N N N N N N N Y N 9
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a
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a N N N N Y N N Y Y N N N N Y Y N Y N N N N N N Y N 7
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      <p>s
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P N N N N N N N H H H A A A A H H H C C C C S S I S ta
P E E E E E E E C C C L L L L C C C O O O O R R H I o
A G G G G G G G S S S P P P P A A A S S S S F F P D T</p>
    </sec>
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