# mCell: Facilitating Mobile Communication of Small Groups

Authors: Jyri Virtanen; Merja Haveri; Jan Blom; Jonna Häkkilä; Mikko T. Tarkiainen
Journal: Advances in Human-Computer Interaction
 (2008)

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## Abstract

Mobile communication technology offers a potential platform for new types of communication applications. Here, we describe the development and experiences with a mobile group communication application, mCell, that runs on a mobile phone. We present the underlying design implications, the application implementation, and a user study, where three groups used the application for one month. The findings of the user study reveal general user experiences with the application and show different patterns of usage depending on the social setting of the group and how the preferred features vary accordingly.


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## Body

## 1. Introduction

The evolution of Internet and
cellular technology has given rise to various forms of computer-mediated
communication (CMC). Particularly, email, instant messaging (IM), mobile
telephony, and SMS have become widely adopted communication means. These
breakthroughs are recent, with the main advances taking place primarily in the
course of the 1990s.Rise of mobile Internet could be
seen as a factor contributing to yet further changes in the way people use
communication technologies. As more and more mobile devices are able to connect
to the Internet, various forms of IP-based CMC, such as IM and voice over IP
(VoIP), will make their way to the mobile domain. Overall, this development
implies that individuals will have a multitude of ways to be in touch with
their social networks, through an increasing number of platforms and
modalities. As Barlow et al. [1] state, “with the development of the Internet,
and with the increasing pervasiveness of communication between networked
computers, we are in the middle of the most transforming technological event
since the capture of fire.”The trend for increased
communication possibilities has led to several interesting social implications,
such as the elevation of the status of social networks. Most contemporary Western
Communities do not resemble preindustrial villages for they are socially
diverse, sparsely knitted, and well
connected to the outside world [2]. Wellman argues that, at least partly due
to fact that computer networks are social networks spanning large distances,
there has been a conceptual revolution moving from defining community in terms
of space, neighborhoods, to define
it in terms of social networks [3].Communication technology has evolved rapidly in the recent
years contributing to the networked nature of today’s world. With increases in
the number of interconnected computing platforms and in the extent to which
social networks are present in people’s everyday life, it is more than likely
that also the near future will witness emergence of novel forms of CMC. It is
impossible to predict the exact nature of this evolution and consequently, determining
the design space of new communication technologies can be challenging. However,
trialing with new group communication concepts may give important information
for the designers of the future communication applications.We have examined mobile users’ communication with their
social network with a novel mobile phone application, mCell, which supports
different types of group communication styles and which implements a novel
technical solution as it is based on communication server running on an S60 mobile phone. In
this paper, we present the concept of mCell and the design implications behind
it, describe the technical implementation and the design process, and report
the findings of a user study involving three different social groups.


## 2. Related Work

CMC has several roles in terms of
supporting an individual’s social network. On one hand, it enables a pervasive
connection to one’s strong ties [4]. On the other hand, Internet services, such
as IM and social networking tools (see, e.g., https://www.orkut.com/), are suitable for
branching new connections and expanding beyond one’s core group. Mobile communication technology has enabled people to be connected to their social networks independently of their current context and has
affected, for example, the communication patterns of mobile workers [5], as it
offers new ways to support both synchronous and asynchronous communications
between users.Text messaging has become an
everyday phenomenon and has a big role in mobile communication practices.
Teenagers’ reasons for the use of SMS are strongly grounded in their social
context [4]. For instance, a densely knitted group of friends can utilize SMS for communication
coordination, activity planning, and general chat [4]. Text messaging supports
flexible way to manage social network and to facilitate social identity. It
offers the sender better means to express themselves, for instance in order to
overcome shyness and control the self-presentation [6]. Camera phones and
multimedia messaging service (MMS) have enabled sharing of the pictorial information via mobile
communication technology and added to the existing text messaging culture. In a
study on cameraphone use, Kindberg et al. [7] describe users’ behavior with
capturing and sharing the images and report, for example, on how sharing of
mutual social experience is one of the key motivators for taking and sharing
photos.In a long term study on Blackberry
users, Peters and ben Allouch [8] report on findings how mobile communication
technology affects on boundaries between work and personal life by fading the
distinction between the two contexts, as the technology is used simultaneously
for personal and business purposes. Also managing social networks with mobile
communication technology becomes intrinsic over time [8]. The ability for
asynchronous communication in mobile context may have an effect on the practices in computer supported collaboration, as demonstrated in the study by Pinelle and Gutwin. In [9], they have studied mobile groups and
collaboration in settings of home healthcare work, where the users have adopted
a loosely coupled collaboration style.Whereas mobile messaging culture
supports maintaining the social network by facilitating typically the
communication between two users at a time, currently the PC domain hosts better
tools for group communication, providing, for example, multiuser chats and
online discussion forums. Instant messaging happening in PC domain is a
practice that has been commonly adopted by large user groups in both work and
leisure settings. For teenagers, IM allows conversing outside the traditional
places and times, and conversation windows are often kept open even if the
conversation is added only now and then [10]. Isaacs et al. [11] have studied the
use of IM in workplaces and report on two main styles of use, working together
and coordinating. IM is also used for initiating the use of other communication
media, such as calling [11]. The use of IM in public displays at a workplace has
also been trialed, and balancing the public and personal aspects in social
interaction is shown in the use of IM, for example, with public announcements versus private
messages [12].Most of the research concerned with computer-supported
communication and management of social networks has so far concentrated on
reporting the findings on usage culture with existing technology, which often
concentrates on one medium, for example, SMS or PC chat. Moreover, the
communication means for mobile context have not been designed to support group
but to support person-to-person communication. Our research diverges from the existing
research into two matters. Firstly, it introduces a novel mobile application that has been
designed to support group communication in mobile context. Secondly, it concentrates on charting phenomena which this new type of communication means brings up in order to
better facilitate the further design of such applications.


## 3. mCell Design Space

Upon starting the project, two
layers contributed to defining the scope of the concept to be designed. On one
hand, user layer was associated with stipulating the potential user group as
well as generic motivations of use. On the other hand, technical layer
articulated the technical enablers on top of which the concept was to be
incorporated.


### 3.1. User Layer

The section above was concerned
with conceptualizing communication from the perspective of social networks. In
line with this, we decided to aim our communication concept at the central part
of the network, namely, the highly interconnected core. Examples of such core
groups, or cliques, could include, for example, local peer groups, hobby groups, or
colleagues working in the same team. To be able to focus on an even narrower
segment of users, we further restricted our scope to cover young, mobile savvy
adults. Several reasons justified this approach:(i)
young people in cities around the globe spend increasing amount of time with their friends, forming networks that Ethan Watters has coined “urban tribes” [13];(ii)
young adults have a relatively large social network and are disposed to utilize various forms of CMC to manage them;(iii)
younger technology users are inclined to try out new technologies and try to differentiate from the mainstream through their selection of communication means;(iv)
technology adoption correlates strongly with young age—for example, percentage of Internet users decreases when progressing to older age groups.
On the basis of the above
assumptions, we reasoned that focusing on young adults would enable us to learn
about the behavior of a segment of users that appropriates, from a relatively
large selection of tools, the relevant ones for the purposes of the given
group. We thus assumed that insight gained from this particular category of
users may apply to the more general user population in the future.


### 3.2. Technical Layer

As for the enabling technology,
earlier work has been done in porting Apache web server to S60 Symbian mobiles
devices and an HTTP access solution from the Internet to the server has been
developed [14]. This platform made it possible to develop a web forum which was
to be hosted on a mobile device and accessed from anywhere in the Internet with
a usual web browser. Our assumption was that such a mobile web forum would
serve a relatively small core group of, for example, ten people.This technical choice was
encouraged by the fact that the content of the communications would remain
private to the group since nothing was to be stored to network server out of
the group’s control. It also made it possible to integrate the web forum with a
user’s contact book information seamlessly in order to define the members of
the group.The choice also introduced
challenges to the user experience such as the unequal share of cost of use
among the group members, battery consumption, and service availability if the
server device is turned off sometimes.


## 3.1. User Layer

The section above was concerned
with conceptualizing communication from the perspective of social networks. In
line with this, we decided to aim our communication concept at the central part
of the network, namely, the highly interconnected core. Examples of such core
groups, or cliques, could include, for example, local peer groups, hobby groups, or
colleagues working in the same team. To be able to focus on an even narrower
segment of users, we further restricted our scope to cover young, mobile savvy
adults. Several reasons justified this approach:(i)
young people in cities around the globe spend increasing amount of time with their friends, forming networks that Ethan Watters has coined “urban tribes” [13];(ii)
young adults have a relatively large social network and are disposed to utilize various forms of CMC to manage them;(iii)
younger technology users are inclined to try out new technologies and try to differentiate from the mainstream through their selection of communication means;(iv)
technology adoption correlates strongly with young age—for example, percentage of Internet users decreases when progressing to older age groups.
On the basis of the above
assumptions, we reasoned that focusing on young adults would enable us to learn
about the behavior of a segment of users that appropriates, from a relatively
large selection of tools, the relevant ones for the purposes of the given
group. We thus assumed that insight gained from this particular category of
users may apply to the more general user population in the future.


## 3.2. Technical Layer

As for the enabling technology,
earlier work has been done in porting Apache web server to S60 Symbian mobiles
devices and an HTTP access solution from the Internet to the server has been
developed [14]. This platform made it possible to develop a web forum which was
to be hosted on a mobile device and accessed from anywhere in the Internet with
a usual web browser. Our assumption was that such a mobile web forum would
serve a relatively small core group of, for example, ten people.This technical choice was
encouraged by the fact that the content of the communications would remain
private to the group since nothing was to be stored to network server out of
the group’s control. It also made it possible to integrate the web forum with a
user’s contact book information seamlessly in order to define the members of
the group.The choice also introduced
challenges to the user experience such as the unequal share of cost of use
among the group members, battery consumption, and service availability if the
server device is turned off sometimes.


## 4. mCell Design Process

The mCell design process started
with a user research stage to produce a set of user-centric requirements. In
line with the user layer considerations of the previous section, we recruited
two sets of users, five people in each. One set consisted of mobile IM users
and the other one consisted of IRC users, both in Finland.First the users were interviewed
about their communication habits and the nature of tools used. Then they were asked
to maintain diaries to record the group-based communication during ca. 20 days.
Finally the users were interviewed again, elaborating on the communication topics
and motivations, using the diaries as a basis.It was observed that real-time
IP-based communication tools, such as IM and IRC, eat up the time and money
invested in mobile phone calls, SMS, and email. Factors contributing to this
change are based both on technological (broadband access and flat fee IP-based
communication, surging uptake of IM technologies) and lifestyle issues
(constant access to computer while at home and being constantly online). Real-time
communication was characterized by multimodality (seamless coexistence of
various channels) and pervasiveness (real-time channels constantly at least in
a peripheral role, mobile use). All interviewees were able to use an ensemble of
CMC tools in a seamless way, for example, discussing the same cognitive thread
over multiple channels.Several themes in communication that were
linked to group-level needs were
observed as follows:(i)
facilitating the existence of a group that used to be local (e.g., high
school mates wanting to
keep in touch when moving apart after graduation);(ii)
coordinating mutual
activities and maintaining situational awareness of group members’ short-term
plans;(iii)
discussing mutual activities retrospectively (e.g., discussing the game
after an online game session or talking about what happened at a party previous
night);(iv)
group cohesion through
humour and competition.Table1 summarizes the main user research findings, the design drivers, and features conducted from them.Table 1
User research findings and conducted design drivers and features.
User research findingDesign driverFeature supporting the driverBecause of IM, communication with social network has become pervasiveEnabling pervasive communication with the groupAllowingmCell to be used through both PC and mobileGroup members use multiple tools to facilitate a single cognitive thread. The more urgent the need for response, the greater the tendency to use real-time communicationSupporting use of multiple communication methodsIncluding several communication methods within one channelSupporting both real-time and non-real-time usesIM is currently lacking effective session convergence featuresCreating hooks to support emergence of real-time interactionSession convergence features, for example, SMS invitationsSome technologically savvy IRC groups configure bots that record the use of the IRC channelSustaining group cohesionCreating a metalevel where the group can monitor how it is using the channelThe user research stage was
followed by a consolidation stage where the technical layer of the mCell design
space was consolidated with the user-centric requirements, and the final
concept was selected.


## 5. mCell Concept

mCell is a group communication
portal hosted in a mobile phone of one group member. Members of the group can
access the portal by using any Internet connected terminal, mobile or PC,
equipped with a web browser. One phone can host several mCell portals typically
targeted for different groups, for example, one for family, one for friends,
and so forth. The mobile phone hosting mCells has an application to manage
them, called mCell Manager.


### 5.1. mCell Manager Features

The mCell Manager application can
be used to create, modify, and delete mCell portals. When mCell portal is
created, it is given a name and its members are specified. mCell Manager
enables selecting the members from the already existing contact items in the
mobile phone. Once a new mCell portal is activated, mCell Manager sends
invitations to its members. If the contact item related to a member includes a
mobile phone number, an SMS invitation is sent to his/her phone. In addition,
if the contact item includes an email address, an invitation is also sent to
that address. The invitations contain the name and the URL of mCell, member’s
personal username, and password to access it.


### 5.2. mCell Portal Features

The mCell portal has the following main features:(i)
mFocus,(ii)
mLine,(iii)
mBoard,(iv)
mTivity,(v)
Members.
Figure 1 illustrates the mCell user interface main view with the key application elements.Figure 1
mCell UI main view.mFocus ia a banner displaying a short message to all members in a
visible place on the mCell main page. The message can be modified by all
members. The postulated user benefit is effective information dissemination
within the group.mLine is a channel for real-time text-based chat. Upon entering
mLine, ten latest messages or actions (entries or exits of users) are shown to
a user so as to acquire a situational awareness of the status of the chat. It
is also possible to see which members are on-line, and if they are accessing
the service through a mobile or a PC. Members not currently logged on can be
invited via SMS messages generated by mLine. The postulated uses are planning
of events taking place in the near future, and general chitchat.mBoard is a channel for non-real time, threaded discussion. The mCell
members can create topics, post, and read messages in them. It is also possible
to attach files, for example, pictures taken with a camera phone, to the
messages. An mBoard RSS feed is provided to ease detecting of new messages.
Obsolete topics can be deleted or archived to mTivity (see below). The
postulated uses of mBoard are planning of mutual events when there is still
ample time left, and reflecting on personal issues.mTivity is an mCell activity tracker. It displays activity figures on
a group and on a member level, and statistics about the longest and the most
visited mBoard threads. Friendly competition is encouraged by displaying the
most active members concerning, for example, mLine, mBoard, and overall mCell
usage. Viewing of “golden oldies” content saved from mBoard is also provided.
The postulated effect of mTivity is to facilitate channel sustainability and
group cohesion.Members is a list of the group members’ names on the main page of mCell.
Online/offline status and currently used terminal type (a mobile or a PC) of
each member are indicated by different icons. The postulated benefit is the
potential to see which members are most likely able to participate in the mLine
chat.


## 5.1. mCell Manager Features

The mCell Manager application can
be used to create, modify, and delete mCell portals. When mCell portal is
created, it is given a name and its members are specified. mCell Manager
enables selecting the members from the already existing contact items in the
mobile phone. Once a new mCell portal is activated, mCell Manager sends
invitations to its members. If the contact item related to a member includes a
mobile phone number, an SMS invitation is sent to his/her phone. In addition,
if the contact item includes an email address, an invitation is also sent to
that address. The invitations contain the name and the URL of mCell, member’s
personal username, and password to access it.


## 5.2. mCell Portal Features

The mCell portal has the following main features:(i)
mFocus,(ii)
mLine,(iii)
mBoard,(iv)
mTivity,(v)
Members.
Figure 1 illustrates the mCell user interface main view with the key application elements.Figure 1
mCell UI main view.mFocus ia a banner displaying a short message to all members in a
visible place on the mCell main page. The message can be modified by all
members. The postulated user benefit is effective information dissemination
within the group.mLine is a channel for real-time text-based chat. Upon entering
mLine, ten latest messages or actions (entries or exits of users) are shown to
a user so as to acquire a situational awareness of the status of the chat. It
is also possible to see which members are on-line, and if they are accessing
the service through a mobile or a PC. Members not currently logged on can be
invited via SMS messages generated by mLine. The postulated uses are planning
of events taking place in the near future, and general chitchat.mBoard is a channel for non-real time, threaded discussion. The mCell
members can create topics, post, and read messages in them. It is also possible
to attach files, for example, pictures taken with a camera phone, to the
messages. An mBoard RSS feed is provided to ease detecting of new messages.
Obsolete topics can be deleted or archived to mTivity (see below). The
postulated uses of mBoard are planning of mutual events when there is still
ample time left, and reflecting on personal issues.mTivity is an mCell activity tracker. It displays activity figures on
a group and on a member level, and statistics about the longest and the most
visited mBoard threads. Friendly competition is encouraged by displaying the
most active members concerning, for example, mLine, mBoard, and overall mCell
usage. Viewing of “golden oldies” content saved from mBoard is also provided.
The postulated effect of mTivity is to facilitate channel sustainability and
group cohesion.Members is a list of the group members’ names on the main page of mCell.
Online/offline status and currently used terminal type (a mobile or a PC) of
each member are indicated by different icons. The postulated benefit is the
potential to see which members are most likely able to participate in the mLine
chat.


## 6. mCell Prototype

The Apache web server ported to
Series 60 Platform on Symbian OS was primarily tested with the Nokia 6630 phone
model, so it was also the choice for the mCell prototype. The main software
components which were needed to be implemented for the prototype were the mCell
Manager application and the scripts to generate dynamically the group
communication portal web pages. The portal pages were designed and tested to be
used with the browser of the Nokia 6630 mobile phone which supports XHTML MP
1.1, and, although this model was chosen for prototyping purposes, any browser
with at least the same capabilities could be used to access them as well.


### 6.1. mCell Manager

mCell Manager, as described by the mCell
concept, is a phone application with a UI to create, modify, and delete mCell
group communication portals. In practice, mCell Manager writes mCell
information (name, members, status) to an mCell database in the phone. That
database is then accessed by the scripts to generate mCell portal web pages.
The mCell database does not duplicate members' contact data but only refers to
the data in the Contacts database of the phone.mCell Manager was implemented as a
native Symbian C++ application to be able to access all the necessary Symbian
and Series 60 APIs. For example, using C++ made it possible to utilize a
service provided by the Contacts application of the phone for displaying a list
of its contact items (view switching). That was helpful to enable picking up mCell
members from the already existing contact items in the phone. All the native UI
classes are also available in the C++ implementation, like double item
listboxes needed in mCell Manager. In addition, mCell Manager required access
to the Symbian messaging interfaces (SMS and MMS) to be able to send mCell invitations
both to mobile phone numbers and email addresses. That was also best supported
by C++ APIs.A side effect of comprehensive
functionality of Symbian C++ APIs is that development is also more complex, and
thus slower. In order to meet the tight schedule requirements for the mCell
prototype, the Application Wizard, example applications of the Series 60 SDK,
and Forum Nokia were fully utilized. That proved to be important to speed up
the development.


### 6.2. mCell Portal Scripts

The Apache web server ported to
Series 60 also contains mod_python, an Apache module that closely integrates
Python with Apache [15]. The porting of that module was, for its part, enabled
by Python for S60 [16], which provides a scripting solution for a subset of the
Symbian C++ and Series 60 APIs. As Python is an effective programming language,
suitable for prototyping, and also because Python for S60 functionality was
found to be sufficient for mCell portal needs, we decided to implement the
portal scripts in Python.A publisher handler of mod_python
allows access to functions within a Python module via URLs. It is a good way to
avoid writing your own handlers and focus on rapid application development, so
the publisher handler was very useful for the mCell prototype development. In
addition, mod_python allows to tell Apache to call an authentication handler
implemented as a Python module instead of using the Apache password and
configuration file-based authentication and authorization. By means of this
feature it is possible to utilize the information in the mCell database for
authentication and authorization directly, and avoid the manual or programmatic
modification of Apache password and configuration files.


## 6.1. mCell Manager

mCell Manager, as described by the mCell
concept, is a phone application with a UI to create, modify, and delete mCell
group communication portals. In practice, mCell Manager writes mCell
information (name, members, status) to an mCell database in the phone. That
database is then accessed by the scripts to generate mCell portal web pages.
The mCell database does not duplicate members' contact data but only refers to
the data in the Contacts database of the phone.mCell Manager was implemented as a
native Symbian C++ application to be able to access all the necessary Symbian
and Series 60 APIs. For example, using C++ made it possible to utilize a
service provided by the Contacts application of the phone for displaying a list
of its contact items (view switching). That was helpful to enable picking up mCell
members from the already existing contact items in the phone. All the native UI
classes are also available in the C++ implementation, like double item
listboxes needed in mCell Manager. In addition, mCell Manager required access
to the Symbian messaging interfaces (SMS and MMS) to be able to send mCell invitations
both to mobile phone numbers and email addresses. That was also best supported
by C++ APIs.A side effect of comprehensive
functionality of Symbian C++ APIs is that development is also more complex, and
thus slower. In order to meet the tight schedule requirements for the mCell
prototype, the Application Wizard, example applications of the Series 60 SDK,
and Forum Nokia were fully utilized. That proved to be important to speed up
the development.


## 6.2. mCell Portal Scripts

The Apache web server ported to
Series 60 also contains mod_python, an Apache module that closely integrates
Python with Apache [15]. The porting of that module was, for its part, enabled
by Python for S60 [16], which provides a scripting solution for a subset of the
Symbian C++ and Series 60 APIs. As Python is an effective programming language,
suitable for prototyping, and also because Python for S60 functionality was
found to be sufficient for mCell portal needs, we decided to implement the
portal scripts in Python.A publisher handler of mod_python
allows access to functions within a Python module via URLs. It is a good way to
avoid writing your own handlers and focus on rapid application development, so
the publisher handler was very useful for the mCell prototype development. In
addition, mod_python allows to tell Apache to call an authentication handler
implemented as a Python module instead of using the Apache password and
configuration file-based authentication and authorization. By means of this
feature it is possible to utilize the information in the mCell database for
authentication and authorization directly, and avoid the manual or programmatic
modification of Apache password and configuration files.


## 7. User Study Setup

### 7.1. Method

To evaluate the mCell application
and to chart the practices users developed with it, a user study was arranged.
We selected three groups of four, five, and six people to use the application
for one month. The aim was to find out how well mCell supported group
communication and what kind of groups could benefit from it the most. We were
also interested in clarifying if mCell truly suited to mobile devices: was it
feasible to keep the server on a phone and what problems and possibilities did users
find in it? In addition to the generic results, we aimed to analyze the
problems and possibilities in the feature level.The study was conducted in February 2006 in Finland, and the groups used the
devices with mCell for a month uninterrupted. The trial period started by
giving all groups individual briefings, where the group members were explained some of the
basic features of mCell. The participants were also encouraged to use the
application in a way that they discovered to fit best their own habits and
purposes. A short midway questionnaire was sent to all the participants in the
middle of the trial to remind them about mCell and the features it has, and
after a month of using mCell all groups were interviewed about their
experiences. Each device also automatically collected logs of the mCell
use during the one-month use period.


### 7.2. Participants

For the user study, we wanted to
find groups of approximately five people having constant need for sharing
information between each other. The groups were chosen so that the group
members were able to stay within 3G network coverage area at least for the most
parts of the study. The participants had also to commit on using the given
devices as their only mobile phones for the time of the study.When selecting the groups,
attention was paid not only to the group but also to the suitability of the
individual group members: they all had to be active SMS users and have no
problems using standard phone keypad for text entry. In addition they needed to
have PCs in use and have the willingness to operate the mCell application on
both devices. One criterion was also the familiarity with S60 mobile phones, so
the study results would not get affected by the different level of skills in
using the devices.The trial was conducted with three
teams—referred here as
Family, DollHouse, and Business teams—which differed
from each other in
a number of aspects (different ages, gender divisions, etc.), Table2. The
first team was a family of six people, two parents and four children between
the ages of 10 to 16. The second team consisted of women with small children.
The connecting factor in their case was a hobby of building dollhouses and
accessories and living in the same region. The third team was a small IT
company employing only men. They shared their work tasks but were located in
different offices and even in different cities.Table 2
Participating groups (F = female, M = male).
TeamNo. of membersGenderAge rangeT1—the Family6F: 2; M: 412–46T2—the DollHouse club4F: 431–40T3—the small IT company5M: 531–39The teams were quite scattered based on their location in Finland. The Family team lived in Tampere,
DollHouse team members in Jyväskylä area. The Business team’s IT company was located in Helsinki, although the team members lived all across Southern Finland.


## 7.1. Method

To evaluate the mCell application
and to chart the practices users developed with it, a user study was arranged.
We selected three groups of four, five, and six people to use the application
for one month. The aim was to find out how well mCell supported group
communication and what kind of groups could benefit from it the most. We were
also interested in clarifying if mCell truly suited to mobile devices: was it
feasible to keep the server on a phone and what problems and possibilities did users
find in it? In addition to the generic results, we aimed to analyze the
problems and possibilities in the feature level.The study was conducted in February 2006 in Finland, and the groups used the
devices with mCell for a month uninterrupted. The trial period started by
giving all groups individual briefings, where the group members were explained some of the
basic features of mCell. The participants were also encouraged to use the
application in a way that they discovered to fit best their own habits and
purposes. A short midway questionnaire was sent to all the participants in the
middle of the trial to remind them about mCell and the features it has, and
after a month of using mCell all groups were interviewed about their
experiences. Each device also automatically collected logs of the mCell
use during the one-month use period.


## 7.2. Participants

For the user study, we wanted to
find groups of approximately five people having constant need for sharing
information between each other. The groups were chosen so that the group
members were able to stay within 3G network coverage area at least for the most
parts of the study. The participants had also to commit on using the given
devices as their only mobile phones for the time of the study.When selecting the groups,
attention was paid not only to the group but also to the suitability of the
individual group members: they all had to be active SMS users and have no
problems using standard phone keypad for text entry. In addition they needed to
have PCs in use and have the willingness to operate the mCell application on
both devices. One criterion was also the familiarity with S60 mobile phones, so
the study results would not get affected by the different level of skills in
using the devices.The trial was conducted with three
teams—referred here as
Family, DollHouse, and Business teams—which differed
from each other in
a number of aspects (different ages, gender divisions, etc.), Table2. The
first team was a family of six people, two parents and four children between
the ages of 10 to 16. The second team consisted of women with small children.
The connecting factor in their case was a hobby of building dollhouses and
accessories and living in the same region. The third team was a small IT
company employing only men. They shared their work tasks but were located in
different offices and even in different cities.Table 2
Participating groups (F = female, M = male).
TeamNo. of membersGenderAge rangeT1—the Family6F: 2; M: 412–46T2—the DollHouse club4F: 431–40T3—the small IT company5M: 531–39The teams were quite scattered based on their location in Finland. The Family team lived in Tampere,
DollHouse team members in Jyväskylä area. The Business team’s IT company was located in Helsinki, although the team members lived all across Southern Finland.


## 8. User Study Results

### 8.1. Context and Content of the Use

The places where mCell was used
varied a lot between the teams. The business team members all used mCell only
when working from their home offices. This was due to the fact that they would
be interacting with their colleagues and therefore perceived that mCell usage
felt more like work to them. The group described their mCell use as “business
orientated chitchat,” meaning that they did not really talk about ongoing work
activities. The discussion was more on a general level, but still somehow
linked to the company affairs. The messages relating to work topics were about
issues that were not quite urgent, since no one knew how actively the others
were checking the messages. The work-orientated usage can also be noticed from
the application logs, which show that only little conversation took place in
the evening and none at night, Figure2.Figure 2
Average number of mCell entries per person during one-month study period.The members of the DollHouse team
used mCell mainly during day time, which was due to their lifestyle: “We are
all married with children and need to sleep at night, might be different for a
group of teenagers who stay up late at night.” One of the DollHouse team members said that she used mCell a lot in
the toilet where she could have a break from her kids and concentrate on the
messages.Content-wise, the DollHouse team’s
manner of using mCell differed from the other teams. Contrary to the other
teams, the discussions between the DollHouse team members were mostly factual.
This was also a major difference between the male and female dominated groups, that
is, Business and DollHouse groups, respectively. The DollHouse group exchanged
only some chat like messages, as most of their discussions were based on actual
topics, such as setting up an exhibition, agreeing on meetings times, sharing
tips on how to build new items for the doll houses, and so forth. The Business
group only used mCell to say hello to each other in a more testing type of
setting. In addition, the conversations of these two groups varied not only in
the aspect of chatting versus sharing factual information, but in sensitivity
level also, as explained further in Section8.3.Whereas the DollHouse team members
used mCell mostly from their homes, this was not a beneficial use domain for
the Family team because “they all were at home anyway.” Thus, the Family team’s
use was then strictly limited to schools and workplaces. The Family team
claimed that since they mainly used mCell at school and work, the only time mCell
was ever used was the day. Interestingly, this subjective perception the team
had of themselves is not supported by the data gathered from the application
logs; see Figure2. The team members said their communication through mCell was
generally only chatting. They used SMS for informative messages whereas mCell
was used merely for keeping in touch and killing time.The
average number of mCell entries per person recorded in the application log is illustrated in Figure2. The figure shows also how the use times were distributed in each group.The mobility of mCell usage was
considered more important in the DollHouse than in any other team. Other teams
thought they might not need the mobility too much since they had frequent access to the Internet.
In the DollHouse group, the participants appreciated the mobility, as for them
an Internet access without constant disturbances was not so easy to arrange
because all of them had small children. One of the participants even mentioned that
she really liked mCell for the fact that it allowed her to get a private moment
for herself and her hobby as she could use the application in the bathroom with
the door locked, and her children would not get there to disturb her.


### 8.2. Used Features

Both the DollHouse team and the
Business team used mainly mBoard in their communication, whereas the Family
team found no use for it and concentrated on using mLine only. DollHouse team
members as well as the Business team members said that they would not use mLine
as they were always there alone. Moreover, they did not want to disturb others
by inviting them to a chat, when they could just leave a message on mBoard
waiting for the others to login. The family members were not so shy about
disturbing each other and invited each other frequently to the mLine chat. They
also kept themselves logged in most of the time so they could join active chats
any time.In the following, the experiences
the users had with different mCell features are described.mBoard was
generally considered a very good tool for small groups, and the  concept itself seemed to work well in
the  context of small group
communication. When trying to estimate potential future concerns, it was
pointed out that with larger user groups, mBoard could feel too crowded and the
user could have difficulties in perceiving the message hierarchies and
navigating in them. An example of a conversation thread taking place in mBoard
is illustrated in Figure 3.Figure 3
Screenshot of an mBoard conversation thread.mLine was
seen as something made for much larger groups than the ones in this trial. The
fact that there hardly ever was anyone else logged in made them feel like it
would require more users. Only the Family team members invited each other
frequently to join the chats, whereas other teams felt like they would be
disturbing others with their not-so-important chats. This might be due to the family
members being more familiar with each other and therefore not as worried of
disturbing each other as the other teams and their members. But also the size
of the Family team being the largest in this trial played an important role in
how useful the chat feature was considered. However, the participants who used
mLine said that it was too difficult to follow the chat with many people
participating in it. The finding highlights the limitations set by the small
screen size, and on the other hand also implies the difficulties larger user
groups might have with the application. Interestingly, once the family members
had learned to use mLine they were reluctant to learn other parts of the
application even though the most technology experienced member of the family
once suggested changing to mBoard. Figure 4 shows an example chat in mLine.Figure 4
Screenshot of an mLine chat.mFocus, mTivity, and Member features had a significantlylesser role in the use of the
mCell application, and they were mostly perceived as indifferent. None of the
participants used mFocus—only the server
owners had sent a couple of messages with it. With mTivity, all
participants reported that they had had a look at what the feature was, but
none of them had developed any habit of checking it, and for their use purposes
the feature was seen as insignificant. The situation was the same with Members,
although here it was commented that the feature would have been used more if it had
shown online status of the team members (as this had not been implemented into
the application).


### 8.3. Privacy and Trust

The
questions related to privacy and trust brought up interesting observations. As
the study was run as a research trial with noncommercial software, participants
from every group had concerns about the research team accessing to their
discussions (although they had been explained this was not the case). The
Family team participants argued that they would not have been worried if they
had bought the application themselves. However, the privacy element was also
something that changed very quickly during the study period, and despite the
concerns in the beginning, after few days of use the Family team did not care
if their messages were read or not.The
DollHouse team did not care about privacy issues at all. All of the members had
participated also in larger web-based discussions about dollhouses and two of
them even wrote a public blog about similar issues. Thus they were not worried
about other people reading their conversations in mCell either. Although much
of their conversation was factual and about practical things, the DollHouse
team members also shared some very private things about themselves in their
conversations (e.g., about pregnancy). Still they claimed that they would not
mind if others would
have read the conversations.The
Business team on the other hand was the opposite to the DollHouse team in privacy issues: they felt
they had to protect their business sensitive information and therefore used mCell
only for general chitchat to minimize the risk of outsiders getting their
information.The server
being on one phone created more trust on privacy. The participants perceived
that as there was only one person in control of the server, and this person was
known to all, it was relatively easy to trust that there would be no outsider
online. In addition, the Family team stated that they would have enhanced the trust
on the privacy if the mCell group had been created and maintained by someone
they know.


### 8.4. Experiences with the Server in the Phone

As the research implemented also a
new technical solution having server in a phone, it was important to gather
user experiences related to this phenomenon as well. However, unfortunately the
benefits of having the server on the phone were not clearly demonstrated, as in
the study the users did not have the possibility to create their own mCells
freely.The server related problems could
be divided into two groups: issues due to current technology and the ones
related to the concept. Power and stability are crucial factors in the use of
the application, as server being down affects to the communication of the whole
group. Now, for example, running out of phone battery was perceived as a major
problem in the use. In addition, the phone’s limited processing power in
comparison to PC caused the server to function somewhat slowly. After the
study, all the three groups agreed that it would be better to have the server
on a PC as the current solution brought too many technical problems—in addition to
power consumption and processing power, running the server on a PC would
eliminate the influence of the existence of the 3G network coverage. Another
major issue was the cost of using the server, which was feared to be too high
for the server owner with the current data transfer costs. The participants
also assumed that PC use would make it easier to share the maintenance
responsibility.The average data transfer per
server during the study was25+25 MB and included barely any images or other
files. None of the trial participants were ready to estimate the monetary cost
of their mCell usage, and they frequently estimated it to be too high. The
server owners had more realistic ideas about the cost of their subscriptions. In the DollHouse
team all but one of the participants had been checking the cost of the mCell
use, although in the study setting they did not have to pay for it themselves.
In the Business group only the server admin had been interested in the cost,
and he had done this not in the sense of actually wanting to know the cost, but
for being curious of the amounts of data transferred.


## 8.1. Context and Content of the Use

The places where mCell was used
varied a lot between the teams. The business team members all used mCell only
when working from their home offices. This was due to the fact that they would
be interacting with their colleagues and therefore perceived that mCell usage
felt more like work to them. The group described their mCell use as “business
orientated chitchat,” meaning that they did not really talk about ongoing work
activities. The discussion was more on a general level, but still somehow
linked to the company affairs. The messages relating to work topics were about
issues that were not quite urgent, since no one knew how actively the others
were checking the messages. The work-orientated usage can also be noticed from
the application logs, which show that only little conversation took place in
the evening and none at night, Figure2.Figure 2
Average number of mCell entries per person during one-month study period.The members of the DollHouse team
used mCell mainly during day time, which was due to their lifestyle: “We are
all married with children and need to sleep at night, might be different for a
group of teenagers who stay up late at night.” One of the DollHouse team members said that she used mCell a lot in
the toilet where she could have a break from her kids and concentrate on the
messages.Content-wise, the DollHouse team’s
manner of using mCell differed from the other teams. Contrary to the other
teams, the discussions between the DollHouse team members were mostly factual.
This was also a major difference between the male and female dominated groups, that
is, Business and DollHouse groups, respectively. The DollHouse group exchanged
only some chat like messages, as most of their discussions were based on actual
topics, such as setting up an exhibition, agreeing on meetings times, sharing
tips on how to build new items for the doll houses, and so forth. The Business
group only used mCell to say hello to each other in a more testing type of
setting. In addition, the conversations of these two groups varied not only in
the aspect of chatting versus sharing factual information, but in sensitivity
level also, as explained further in Section8.3.Whereas the DollHouse team members
used mCell mostly from their homes, this was not a beneficial use domain for
the Family team because “they all were at home anyway.” Thus, the Family team’s
use was then strictly limited to schools and workplaces. The Family team
claimed that since they mainly used mCell at school and work, the only time mCell
was ever used was the day. Interestingly, this subjective perception the team
had of themselves is not supported by the data gathered from the application
logs; see Figure2. The team members said their communication through mCell was
generally only chatting. They used SMS for informative messages whereas mCell
was used merely for keeping in touch and killing time.The
average number of mCell entries per person recorded in the application log is illustrated in Figure2. The figure shows also how the use times were distributed in each group.The mobility of mCell usage was
considered more important in the DollHouse than in any other team. Other teams
thought they might not need the mobility too much since they had frequent access to the Internet.
In the DollHouse group, the participants appreciated the mobility, as for them
an Internet access without constant disturbances was not so easy to arrange
because all of them had small children. One of the participants even mentioned that
she really liked mCell for the fact that it allowed her to get a private moment
for herself and her hobby as she could use the application in the bathroom with
the door locked, and her children would not get there to disturb her.


## 8.2. Used Features

Both the DollHouse team and the
Business team used mainly mBoard in their communication, whereas the Family
team found no use for it and concentrated on using mLine only. DollHouse team
members as well as the Business team members said that they would not use mLine
as they were always there alone. Moreover, they did not want to disturb others
by inviting them to a chat, when they could just leave a message on mBoard
waiting for the others to login. The family members were not so shy about
disturbing each other and invited each other frequently to the mLine chat. They
also kept themselves logged in most of the time so they could join active chats
any time.In the following, the experiences
the users had with different mCell features are described.mBoard was
generally considered a very good tool for small groups, and the  concept itself seemed to work well in
the  context of small group
communication. When trying to estimate potential future concerns, it was
pointed out that with larger user groups, mBoard could feel too crowded and the
user could have difficulties in perceiving the message hierarchies and
navigating in them. An example of a conversation thread taking place in mBoard
is illustrated in Figure 3.Figure 3
Screenshot of an mBoard conversation thread.mLine was
seen as something made for much larger groups than the ones in this trial. The
fact that there hardly ever was anyone else logged in made them feel like it
would require more users. Only the Family team members invited each other
frequently to join the chats, whereas other teams felt like they would be
disturbing others with their not-so-important chats. This might be due to the family
members being more familiar with each other and therefore not as worried of
disturbing each other as the other teams and their members. But also the size
of the Family team being the largest in this trial played an important role in
how useful the chat feature was considered. However, the participants who used
mLine said that it was too difficult to follow the chat with many people
participating in it. The finding highlights the limitations set by the small
screen size, and on the other hand also implies the difficulties larger user
groups might have with the application. Interestingly, once the family members
had learned to use mLine they were reluctant to learn other parts of the
application even though the most technology experienced member of the family
once suggested changing to mBoard. Figure 4 shows an example chat in mLine.Figure 4
Screenshot of an mLine chat.mFocus, mTivity, and Member features had a significantlylesser role in the use of the
mCell application, and they were mostly perceived as indifferent. None of the
participants used mFocus—only the server
owners had sent a couple of messages with it. With mTivity, all
participants reported that they had had a look at what the feature was, but
none of them had developed any habit of checking it, and for their use purposes
the feature was seen as insignificant. The situation was the same with Members,
although here it was commented that the feature would have been used more if it had
shown online status of the team members (as this had not been implemented into
the application).


## 8.3. Privacy and Trust

The
questions related to privacy and trust brought up interesting observations. As
the study was run as a research trial with noncommercial software, participants
from every group had concerns about the research team accessing to their
discussions (although they had been explained this was not the case). The
Family team participants argued that they would not have been worried if they
had bought the application themselves. However, the privacy element was also
something that changed very quickly during the study period, and despite the
concerns in the beginning, after few days of use the Family team did not care
if their messages were read or not.The
DollHouse team did not care about privacy issues at all. All of the members had
participated also in larger web-based discussions about dollhouses and two of
them even wrote a public blog about similar issues. Thus they were not worried
about other people reading their conversations in mCell either. Although much
of their conversation was factual and about practical things, the DollHouse
team members also shared some very private things about themselves in their
conversations (e.g., about pregnancy). Still they claimed that they would not
mind if others would
have read the conversations.The
Business team on the other hand was the opposite to the DollHouse team in privacy issues: they felt
they had to protect their business sensitive information and therefore used mCell
only for general chitchat to minimize the risk of outsiders getting their
information.The server
being on one phone created more trust on privacy. The participants perceived
that as there was only one person in control of the server, and this person was
known to all, it was relatively easy to trust that there would be no outsider
online. In addition, the Family team stated that they would have enhanced the trust
on the privacy if the mCell group had been created and maintained by someone
they know.


## 8.4. Experiences with the Server in the Phone

As the research implemented also a
new technical solution having server in a phone, it was important to gather
user experiences related to this phenomenon as well. However, unfortunately the
benefits of having the server on the phone were not clearly demonstrated, as in
the study the users did not have the possibility to create their own mCells
freely.The server related problems could
be divided into two groups: issues due to current technology and the ones
related to the concept. Power and stability are crucial factors in the use of
the application, as server being down affects to the communication of the whole
group. Now, for example, running out of phone battery was perceived as a major
problem in the use. In addition, the phone’s limited processing power in
comparison to PC caused the server to function somewhat slowly. After the
study, all the three groups agreed that it would be better to have the server
on a PC as the current solution brought too many technical problems—in addition to
power consumption and processing power, running the server on a PC would
eliminate the influence of the existence of the 3G network coverage. Another
major issue was the cost of using the server, which was feared to be too high
for the server owner with the current data transfer costs. The participants
also assumed that PC use would make it easier to share the maintenance
responsibility.The average data transfer per
server during the study was25+25 MB and included barely any images or other
files. None of the trial participants were ready to estimate the monetary cost
of their mCell usage, and they frequently estimated it to be too high. The
server owners had more realistic ideas about the cost of their subscriptions. In the DollHouse
team all but one of the participants had been checking the cost of the mCell
use, although in the study setting they did not have to pay for it themselves.
In the Business group only the server admin had been interested in the cost,
and he had done this not in the sense of actually wanting to know the cost, but
for being curious of the amounts of data transferred.


## 9. Discussion

The problems appearing in mCell
were twofold: problems caused by the technical implementation and problems
caused by the concept itself. From the research point of view, the technical
problems do not have the same level of significance when the technology
develops. However, the design itself can benefit from the concept level
findings.The problems reported with the use
ofmBoard were mostly technical, and although larger user groups might
affect negatively to the information presentation and navigation, no
significant problems were detected for the participating groups. With the
online chat function mLine, one problem with the concept was the barrier
of inviting others to join the chat, and the threshold for inviting others
seemed to be greater than expected. The findings suggest that in order this concept
to be successful, the group members should either know each others very well,
or the groups should be larger to maximize the possibility to have someone
logged into chat at all times. One can speculate that this may have had an
effect even in this study, as the biggest group having the most members (Family
team, 6 members) was the one using mLine. The reason may also lie in a family
type of communication, where only fast real-time communication is needed, when
all other discussions can be handled once the whole family is at home. In a
family, people are also more familiar with each other and do not worry so much
about disturbing with their chat requests. One aspect to the different behavior
of Family group in comparison to other groups can also be the fact that it was
the only one involving minors; teenage members probably have different
communication needs and patterns than adults in their thirties and forties.The results varied a lot between
the groups and therefore it is also interesting to look at the differences in
the group attributes. The Family group was the most differentiating from the
other two as the majority of its members were minors. But the DollHouse group
and the Business group were quite similar in age and education level, and it
was interesting to see that the results were still quite different, may be
partly because of the gender difference.The most eye-catching differences
between the male and the female groups were the attitude toward privacy issues and the type of
communication mCell was used for. DollHouse group was not worried about the
possibility of other people seeing their conversations, whereas the Business
team was constantly bringing it up in the interviews. This can be explained
partially with the information sensitivity, as the DollHouse issues are not
business sensitive like the communication inside a small business. The DollHouse participants shared some very
private things in the conversations, whereas the business team only used mCell
to kill time and chat about nonbusiness issues, sharing jokes and such. Still,
the Business team was the one that was more worried about the possibility for
others accessing their discussions.One reason affecting the types of
conversation could be also the background of the participants. In the DollHouse
group all the women had been using several message boards in the Internet
before and were still very active in using them. The men of the business group
worked in an IT company and were of course very well accustomed to all kinds of
Internet services but were not as active in any discussion forums in the
Internet. It was probably more natural for the DollHouse team to take a new
kind of discussion tool in use as they were so accustomed to having discussions
with such before. This can also be seen in the amount of use of mCell, Figure2.The technical problems with mCell
were mostly related to the occasional events of the server being down, which
caused also majority of the negative feedback in the user study. This problem
can be estimated to become less frequent as the mobile devices will be equipped
with more memory and processing power and the batteries will get better. For
the problems caused by the situations where the server owner was not able to
keep the server on, it would be recommended, for example, to provide a way to
change the server admin inside the team. The maintenance account could be
switched from one phone to another. One design solution could also be that mCell
changed the server in use by itself whenever needed.


## 10. Conclusions

In this paper, we have described mobile communication
application for small groups, mCell, which is based on having a server running
on an S60 mobile
phone. The application fosters several different kinds of communication styles,
that is, online chat, messaging board, list of group members and their activity
tracker, and short, one-line, onscreen messaging. After implementing the
application, we run a one-month user study that involved three groups having 4–6 members in
order to evaluate the application and find out the practices people developed
with such a mobile group communication tool.The user study results indicate that the concept was received
well, and group communication applications are an intuitive and natural way to
extend the communication characteristics of mobile phones. The study also shows
that the practices of how the group communication application is used will vary
between different user groups based on the nature of the group (professional,
family, hobby, etc.), closeness and trust between the group members, members’
earlier experiences with using group communication application, for example, in
the Internet, and their general lifestyle. The results of the study also
revealed that each group found its preferred way of communicating rather quickly and
concentrated its usage
on it while leaving the other features of the application quite untouched. As a
future work, the authors would find it interesting to develop the concept
further and look at the dynamics of group communication in more depth with a
larger user study.



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*Source: 614987-2008-12-16.xml*