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A Social Network Study of the Apple vs. Android
Smartphone Battle
Johannes Bjelland, Geoffrey Canright, Kenth Engø-
Monsen, Pål Roe Sundsøy
Telenor Research and Future Studies
Telenor ASA
Oslo, Norway
Johannes.bjelland@telenor.com
Rich S. Ling
IT University / Telenor ASA
Copenhagen, Denmark / Oslo, Norway
rili@itu.dk
Abstract—In this paper we measure and quantify how
consumer’s choice of smartphones are related to their peers’
smartphone choices. Specifically, we study and compare this
‘social component’ of product adoption for two competing classes
of smartphones: iPhone and Android. This is done by
constructing a proxy of a social network by using anonymous
phone log data from Norwegian mobile phone users, and then
coupling adoption data to this social network. We find that
smartphone adoption is dependent on the underlying social
network both for Android and for iPhone users. Comparing the
two, we see that the effect is strongest for the latter. In addition,
we measure that the core social network is larger for iPhone
users than for Android – Measured by telecom communication,
Apple users have more friends than android users. We also
present results showing urban/rural differences in smartphone
usage.
Social Network Analysis;Viral Marketing; iPhone; Android;
Telecom, product diffusion
I. INTRODUCTION
It has long been known among marketers that our social
network matters when we make purchasing decisions, and that
having positive word of mouth about a product can be a key to
success; see e.g. [1] for a review of studies on social networks
within marketing. Traditionally, data on social networks have
been difficult to collect, but in recent years researchers have
gained access to massive social network data from e.g. online
instant messaging services [8][5] and phone log data
[2][4][3][6][9]. Such data has made it possible to study e.g.
social churn [3], service uptake [2] among telecom customers,
and product adoption on an Instant Messaging network
[8].These studies confirm that consumer behavior is dependent
on the communication network. We have in a recent study [6]
shown how the structure of the adopter network—the social
network of adopters—develops over time, and how social
spreading can be measured by studying this network. In this
paper, we do a comparative study of social spreading effects
for two competing types of smartphones - the Apple iPhone,
and smartphones based on Google’s Android OS.
II. METHOD
Our social network is built by collecting anonymized call data
records, aggregated over a 3-month period, and then using the
communication links (voice and sms) as proxy for the social
relationships. To remove error sources due to ‘non-personal’
relationships we have applied some filtering of the dataset.
E.g. we see that some customers have thousands of contacts
during the three months period. This can be machines set up to
automatically send SMSs, company call-centers or other forms
of extreme calling behavior. Such outlier nodes are filtered out
based on combinations of extreme usage and degree (number
of unique contacts). Only traffic between Telenor customers is
used, calls to other operators are excluded. For this study we
have also included weak links – we also want to include
relations with limited SMS/voice traffic in the period. In total
we end up with a network containing around 2.5 million nodes
and 45 million edges.
Other studies have shown that mobile phone activity is a good
way to measure real social relationships [5]. We also use
handset type data to associate a handset type with each node in
the social network. With these data we can define the
‘adoption network’ – the social network among adopters [6].
This is simply the sub network consisting of adopters and their
common links. We can then study the development of the
adoption network for iPhones (viewed as a single ‘product’)—
as seen in [6]—and, here, for Android phones, over time
(again making no distinction among the various models of
Android phones). These same data allow us to measure
conditional adoption probabilities between neighbors on the
network, which we use as an indicator of social effects.
Finally, we use postcode information—very coarse-grained
geographic information— on subscribers to map smartphone
adoption to geographical areas in Norway.
III. RESULTS
In a previous paper [6], we looked at the growth of the iPhone
adoption network over time, showing clearly the development
of a ‘social monster’—a giant connected component of the
adoption network which shows the fastest growth. We equated
the strength of this monster with the presence of iPhone
adopters in the ‘dense core’ of highly central subscribers—a
sign of success of the product in taking off. Presence in the
dense core is also inevitably associated with a high density of
adopter-adopter links—a sign that the product adoptions is
‘social’. Here, in using the term ‘social adoption’, we do not
attempt to distinguish homophily effects from true inter-
customer influence: we simply seek to measure the tendency
for those who talk together to adopt together.
In Figure 1, we compare the growth of the Apple adoption
network with that of the Android adoption network, on a
quarterly basis. In each case, we start with the quarter in which
the ‘product’ was first launched. While we see no dramatic
difference in the first–quarter picture (Fig 1(a)), it is clear that
already, two quarters later (Fig 1(c)), the Apple ‘monster’
(Largest Connected Component - LCC) is growing much more
rapidly than the Android monster. This holds not only for total
number of adopters in the LCC, but also in terms of their
percentage of all adopters: two quarters after launch, the
Apple LCC has ca 38% of all adopters, while the Android
LCC has around 28%.
For another indicator of social adoption, we look at the
number of inter-adopter links (adoption pairs) in each
adoption network, over time. Figure 2 tracks the number of
adoption pairs for each product, versus the total number of
adopters. The black dotted curve in Figure 2 gives the number
of adopter pairs expected, for the given total number of
adopter pairs on the fixed call network, if adoption was purely
random. We see that both products generate many times the
number of adopter pairs expected from this random reference
model. Thus, both products show significant social adoption—
but, again, the effect is clearly weaker for Android. (The ratio
between the empirical number of adopters, and that number
found in the random reference model, was studied in Ref. [6]
and termed ‘kappa’.)
In Figure 3 we plot yet another indicator of social adoption.
Here we look at
)(kpX
—the conditional probability that,
given that a node has k neighbors adopting product X, the
node in question has also adopted product X.
Since random adoption gives a flat
)(kpX
, the positive slope
of the results in Figure 3 are again taken as evidence for social
effects (of some kind) in adoption—for both products. The
difference between Apple and Android is seen here in that the
Android curve has more weight at small k—flattening out at
large k—while the Apple curve has less weight at small k, but
grows steeply, and almost perfectly linearly, all the way to
k=10. These data were taken in Q3/2011. In this period, the
Apple and Android penetration were approximately equally
(around 18% each). Hence we see that p(k) is
underrepresented at small k (compared to the random case, ie,
a flat line at p(k) = 18%), and overrepresented at large k, for
both products—but the skew is greater for Apple than for
Android. Taking this skew as an indicator of social adoption,
we find again that Apple is ‘more social’ than Android.
Figure 4 shows the two-dimensional conditional probability
),( YXW kkp
that a node has adopted product W = (Apple or
Figure 1
The figure shows the evolution of the iPhone (Red/Left) and Android (Blue/Right) adoption networks during the 3 first quarters after launch of the first
respective brands. The nodes are customer with iPhone(red) and Android (blue). Links indicate communication between the nodes. Figure a) is the quarter when
the handset first appears in the market, b) is the next quarter and c) is third quarter after product launch. Isolated nodes are not shown – i.e iPhone customers that
do not know other iPhone buyers or Android Customers that do not call other Android customers will not appear in this visualization.
Figure 2
The plot shows the number of adoption pairs (Connected customers
adopting same type of handset) vs. the total number of customers having
the brand (x-axis). Red solid line is iPhone, blue stipled line is Android and
black dotted line is the random simulation model.
Android), given that the node has
X
k
neighbors who have
adopted W, and
Y
k
neighbors who have adopted the
competing product. The upper part of Figure 4 shows this for
W = Apple, and the lower part for W = Android. In each case,
the x axis gives the number of neighbors having adopted
product W. Thus we expect (and find) highest weight in the
lower right-hand corner: lots of W neighbors, and few or no
competing neighbors, giving high probability of adopting W.
Hence, qualitatively, neither part of Figure 4 gives a
surprise—and, once again, the observed ‘biasing’ effects on
neighbors are clearly stronger for Apple than for Android.
Inspired by these results, we have examined the geographic
distributions of these two products. Our method here was to
first aggregate Apple and Android adoption totals over
Norwegian postal codes, and then we take the ratio of the two.
Figure 5 shows the results superimposed on a map of Norway.
What we find, very simply, is that Apple is dominating in
Norway’s cities. Since these results are also from Q3/2011,
there are roughly equal numbers of Apple and Android
phones—so that Apple cannot win everywhere. Thus we see a
rather stark urban/rural dichotomy, with Apple dominating the
cities and Android turning up as scattered blue spots in the
countryside.
We conjecture (but have not yet tested) that the high-centrality
users (as measured by eigenvector centrality) are concentrated
geographically in the cities (just as they are concentrated, by
definition, in the dense core of the social network). In any
case, all of the above results give a picture of Apple users as
being more attracted to other Apple users than are Android
users to other Android users—but also, more social in general.
To test this idea, we show in Figure 6 the average degree
centrality of three groups: Apple users, Android users, and the
whole population. The result is clear: while Android users
have slightly higher degree centrality than the whole
population, Apple users have around 50% higher degree
centrality—they are more social, by this definition.
Results from an earlier period confirm this picture. We
measured the number of Apple-Apple links and Android-
Android links (as in Figure 2), but also the number of Apple-
Android links. From these data we can get the average number
of Apple and Android friends an Apple user has—and the
same for an Android user. The result was clear: the average
Apple user had over two times as many Apple friends as
statistically expected from no preference—while all other
results (number of Apple friends of Android users, and
number of Android friends of Apple and Android users) were
Figure 3
The plot shows ego’s handset adoption probability given x number of
alters with same handset. Red solid line is iPhone adoption probability
and blue stippled line is Android. Note that adoption probability increases
strongly with the number of adopting peers.
Figure 4
The plots show the adoption probability for iPhone and Android versus
the number of contacts with iPhone and number of contacts with
Android. Top plot: x-axis is the number of iPhone contacts, y-axis is
number of Android contacts and color intensity is iPhone adoption
probability for ego (Dark is low probability).
Lower plot: Color intensity is ego’s Android adoption probability given x
number of Android contacts and y number of iPhone contacts. At the time
of measurement, market share of iPhones roughly equals that of Android
smartphones.
statistically consistent with no Apple/Android preference. In
short: restricted to smartphone users, we again find that Apple
users have more friends, and a stronger preference for their
‘own kind’.
Using our geographic information on subscribers, we have
displayed the results in Figure 6 in terms of three broad
geographic categories—“urban”, “small town”, and “rural”.
Here we see a clear result that is counterintuitive: for all three
groups of nodes (Apple, Android, all), we find that the average
degree centrality increases steadily as one moves from urban
to small town to rural. This result is not understood. We leave
this question (and the measurement of eigenvector centrality
for these groups) to future work.
IV. SUMMARY AND FUTURE WORK
In previous work [6], we showed strong social effects on the
adoption of iPhones. Our aim in this work was to perform
similar measurements on Android phones, in such a way that
we could compare the two types of Smartphones on the
dimension of social adoption effects. We have looked at: (i)
the growth of the social monster in the dense core of the social
network; (ii) the number of adoption pairs; (iii) the conditional
probabilities for adopting Apple or Android, conditioned on
the adoption numbers for adopting neighbors; (iv) the
distribution of Apple and Android over the Norwegian
geography; and (v) the average degree centrality of each
group. Without exception, our results in all these tests support
the conclusion that social adoption effects are considerably
stronger for Apple than for Android. Furthermore, our degree
centrality results imply that Apple users in general are more
socially active than Android users. It seems that Apple appeals
to this type of very social user; and that Apple users in turn
interact strongly, and preferentially, with one another.
Figure 5
The figure shows iPhone and Android uptake mapped to geography via postcodes: Postcodes with more iPhone users than Android users are colored red. Blue
indicates more Android than iPhone in that area. The arrows point at some of the largest cities in Norway. From west to east: Bergen, Stavanger, Kristiansand,
Oslo and Fredrikstad. The visualization shows that iPhone ‘wins’ the cities and Android dominates in rural areas. b) is a close-up of the area around Oslo – the
largest city, and c) the area around Bergen – the second largest city. iPhone dominates close to the center and in surrounding suburbs.
These results (especially the ‘monster’ results) imply [6] that
Apple users should have higher (eigenvector) centrality than
Android users. We save this question for future work. We also
plan to look further at the intriguing result, seen here, showing
higher degree centrality in rural areas than in urban areas. We
will also look further into if ‘peer pressure’ effects vary
between urban and more rural locations.
Android handsets are manufactured by several producers, with
varying features. A study on how the social adoption varies
among the different Android brands is reserved for future
work.
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Figure 6
Average number of contacts split by customer groups: All, Android users
and Apple Users. The colors indicates location of residency- Urban (grey),
Small town (blue) and Rural (violet).