Characterizing the Technological Evolution of Smartphones: Insights from Performance Benchmarks Qiwei Han Daegon Cho Department of Engineering and Public Policy Carnegie Mellon University Pittsburgh PA 15213 College of Business KAIST Seoul, Korea 02455 qiweih@cmu.edu ABSTRACT Recent technological advancements in smartphone have paved the way for the rapidly growing mobile commerce. As smartphone vendors launch the products with a rich variety of technical features for different end-user market segments, understanding the evolution of these features is of vital importance to all stakeholders in the smartphone industry. We address this issue by exploring technical specifications of smartphones at both the feature and the device level. In particular, we introduce the benchmarks to operationalize the overall performance of smartphone models, such that multidimensional technical features can be quantitatively summarized into a single index. Through the analysis of a comprehensive dataset entailing technical features for smartphone models launched during the years 2012-2015, we show that although certain features have become the standard functionality, the smartphone industry is largely innovative and continues to evolve over time. We believe our findings may provide important insights into the future development and design strategies of smartphones. CCS Concepts •Information systems → Data analytics; •Humancentered computing → Smartphones; Keywords Smartphone; Mobile Technology; Performance 1. INTRODUCTION Smartphones nowadays have quickly replaced feature phones to become the dominant configuration for mobile handsets. Gartner estimates that smartphones account for 82 percent of mobile handset shipment by the end of 2016 [13]. The popularity of smartphones reflects the fast technological evolution of mobile handsets from communication devices with fixed functionalities to general-purpose devices empowered Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from permissions@acm.org. ICEC ’16 August 17–19, 2016, Suwon, Republic of Korea c 2016 ACM. ISBN 978-1-4503-4222-3/16/08. . . $15.00 DOI: http://dx.doi.org/10.1145/2971603.2971635 daegon.cho@kaist.ac.kr by advanced computing capability and network connectivity [25]. In essence, the accelerated convergence of mobile telephony, personal computing and Internet services leads to the emergence of multi-sided technological and commercial platforms that involve interdependent stakeholders, including chipset makers and component suppliers, smartphone vendors, mobile network operators (MNOs), mobile OS and application developers [7]. These stakeholders together contribute complementary innovations and integrate both hardware and software artifacts into smartphones that provide users with “over-the-top” services, such as Internet browsing, video streaming, online gaming, etc. [24]. Meanwhile, the smartphone industry has continuously witnessed that new entrants such as Apple and Samsung outcompete the incumbents for their superior product development and design strategies [14, 31]. This phenomenon leads to both the proliferation of new phone models and high variations of technical features among heterogeneous manufacturers, implying that product differentiation still characterizes this innovative and competitive market [8]. Therefore, smartphone vendors have strong incentives to build the products at the technological edge, because this may create more values in response to the ever increasing performance demanded by the market than merely imitating from competitors [27]. Characterizing the technological evolution of smartphones along a set of features is also of vital importance to other stakeholders in the wireless industry across the value chain. MNOs are challenged by the declining voice and SMS usage and substantial investment in handling network capacity due to the surge in mobile data traffic. As smartphone users have higher willingness to add mobile broadband to tariff plans as add-on services, MNOs endeavor to close the revenue gap by inducing subscribers to adopt more advanced smartphone models and transform tariff structures to become more data-centric [29]. Moreover, mobile application developers heavily rely on the technical features embedded in smartphones as enablers of their services [25]. For example, the market potential for location-based mobile applications would be limited without a large installed base of smartphones equipped with GPS sensors. Lastly, improvement in smartphone features may increase consumer utility and in turn spur widespread adoption [33]. For example, the early success of Apple’s iPhone can be attributed to the enhanced web browser and touchscreen technology that provide its users with a compelling mobile Internet experience and thus generate positive network effects [12, 37]. However, the increasingly sophisticated feature combinations that smartphone vendors leverage to build the prod- ucts for different end-user segments complicates our understandings on how smartphone technologies evolve for the following reasons. First, as smartphones typically contain a rich variety of technical characteristics, the objective evaluation of overall device performance is underexplored. For example, tightly integrated technical specifications such as CPU frequency, memory size and power consumption are at play in partially affecting system performance of a smartphone. Second, comparative measurement of smartphone models across different dimensions (e.g. mobile OS platforms) remains elusive. Third, interactions between smartphone’s hardware components and its built-in software further plague the issue. A wide range of smartphone vendors that appropriate and customize the open standard Android platform may yield different usability even with similar hardware configuration, due to the own proprietary design and engineering process [31]. After all, the combinatorial nature of smartphone related technologies cautions researchers to operationalize features beyond synergies between technical specifications [38]. In this paper, we aim to characterize the recent technological evolution of smartphones. We do so by exploring a comprehensive dataset entailing technical specifications of smartphone models launched during the years 2012-2015 at both the feature level and the device level. In particular, we introduce the benchmarks to operationalize the overall performance of smartphone models, such that multidimensional technical features can be quantitatively summarized into a single index. To the best of our knowledge, this paper is the first attempt that leverages the benchmark to measure the performance of smart devices such as smartphones. We organize the rest of paper as follows. Section 2 provides the overview on the smartphone market and related work on the development of technique features incorporated into the mobile device. Section 3 describes the background of smartphone benchmarks. Section 4 explains the collected dataset of smartphone models with technical specification details. Section 5 demonstrates the technological evolution in terms of the technical feature as well as the overall performance. Section 6 discusses the managerial implication of our findings and future research. 2. 2.1 BACKGROUND AND RELATED WORK Smartphone Market Overview The smartphone marketplace has experienced substantial growth and drastic changes since 2008 with the arrival of Apple’s iPhone and smartphones based on Google’s Android.1 We compile the analyst reports from Gartner through 20082015 to demonstrate the trends using four important market statistics as shown in Figure 1. First, the mobile handset sales worldwide have been steadily growing. In particular, smartphone sales increased by over 10 times, reaching 1.4 billion units and surpassed that of feature phones since 2013 (Fig. 1a). Second, new entrants such as Apple, Google and Microsoft brought core strength from personal computing and Internet industry to build mobile platforms different from incumbents [24]. The long-standing market leader 1 We do not aim to survey the early stage of smartphones as it is beyond our objective. Interested readers may refer to e.g. [7, 8] for historical background of smartphone from PDA since 1990s. Nokia rapidly lost its market share to Apple and Android (e.g. Samsung). Moreover, the market share of top five vendors dropped from 80% in 2008 to 47% in 2015, indicating that mobile handset market has become ever more fragmented (Fig. 1b). Third, the market share by mobile OS can further reflect the fundamental shift in market dominance from Nokia’s Symbian and RIM’s Blackberry to Android and iOS once developed around 2008 [31]. More specifically, Android now represented over 80% of market share and together with iOS (16%) dominated the market, leaving Microsoft’s Windows Phone (2%) far behind even after its acquisition of Nokia (Fig. 1c). Fourth, the increasing availability of mobile applications (commonly known as apps) that users can download from app stores significantly enriches the value of smartphone usage [17]. The annual mobile app downloads are predicted to exceed 220 billion in 2016, of which nearly 14 billion is from paid apps (Fig. 1d). This fact presents exciting opportunities to understand the great potential of mobile commerce by exploring the behavior of mobile app users [11, 21]. 2.2 Development of Mobile Handset Features The development of mobile technology features has been studied within the IS discipline since the feature phone era [28]. Traditionally, new features are first introduced into handset models and further upgraded to result in significant performance improvement. For example, the successive generations of core mobile communication technologies (e.g. from 2G to 3G, etc.) tend to be consistently more preferred over the predecessors [23]. However, features are more often added to the handsets as the complementary functionalities that rarely define generational changes in product evolution [26]. Also, handset manufacturers strategically choose among a set of features to launch products for differentiation purposes [34]. Thus Koski and Kretschmer (2007) identify two distinct strategies for the development of mobile handsets as vertical innovation and horizontal innovation, respectively [26]. The former refers to the incremental improvement to the existing technical features (e.g. battery life), i.e., the quality ranking for all end-users, whereas the latter refers to the technical characteristics (e.g. ringtones) valued by heterogeneous end-user segments differently. They demonstrate that product innovations at feature level occur across both vertical and horizontal dimensions [27]. The emergence of smartphones has redefined the competitive landscape of mobile handset industry through a series of technological developments in both the hardware and software components. In particular, a subset of the features as the results of either vertical or horizontal innovations gains the general acceptance as the standard functionality and physical design [8, 32]. The trend of convergence in technical features is even intensified as Google licensed the Android freely to attract a majority of smartphone vendors to enter the market and launch the products with similar specifications [31]. More recently, smartphone market growth is majorly driven by replacement demand as the penetration rates approach saturation [13], and ones with higher technological sophistication tend to be diffused through the market faster and have longer unit lifetime [35]. Therefore, the industrial dynamics and the heterogeneity of consumer prompt smartphone vendors to continuously improve the quality and performance of existing features and meanwhile introduce new features to serve market niches [8]. (a) (b) (c) (d) Figure 1: Global mobile handset market statistics through 2008-2015 synthesized from Gartner press releases: (a) mobile handset sales; (b) mobile handset market share by vendor; (c) smartphone market share by Operating System; (d) mobile app store downloads. However, current literature only focuses on the existence of technical features incorporated in the handset models but fail to account for the variations in quality and performance of each feature [8, 25, 34, 35]. To capture the evolution of these features, researchers need to objectively measure the performance and allow the comparison across smartphone models. This salient observation leads us to link with another stream of literature that leverages the concept of the benchmark as the performance characteristic. 2.3 Performance Measurement for IT Products The benchmark scores have been used by economists as reliable proxies for the relative quality of numerous complex IT artifacts, such as CPUs [6, 18, 19, 30], desktop computers [4, 5] and laptop computers [9]. In general, benchmark enables the direct measurement of product performance based on actual computational workload tests on routine tasks obtained by a user rather than conventional input characteristics [6]. For example, clock speed (GHz) cannot sufficiently gauge the computational power of CPU due to differences in chip architectures (e.g. non-homogeneity across CPU brands and families). Thus, the use of benchmark may facilitate the performance comparison between different CPU models [19]. Moreover, as the overall performance of computer systems is determined through the interaction of a combination of hardware and software components, the system-level benchmark can quantitatively summarize multidimensional technical specifications into a single index [9]. In particular, such interactions are not easily measurable by accounting for observed technical specifications independently. Benkard and Bajari (2005) show that omitting CPU benchmark may cause a large bias in estimating the quality changes of personal computers due to the unobserved characteristics [4]. However, using the benchmark to operationalize the performance of smartphones remains challenging for its complex underlying synergies between heterogeneous components [10]. In contrast to personal computers, smartphones have even more unobserved performance characteristic (e.g. mobile applications usability) beyond technical specifications [22]. As such, performance measurement on application-architecture interactions should mirror interactive user activities, such as web browsing, gaming and video streaming. Only recent work by Riikonen et al. (2016) suggests that it would be salient to include performance-related variables into the feature set of smartphones to evaluate the technological sophistication, but they do not provide any solid measures either [35]. 3. SMARTPHONE BENCHMARKS Similar to common practices in the computer industry, smartphone benchmark evaluates smartphone performance through workload analysis on different models. Typically, all users can easily install benchmarking tools on their smartphone as mobile apps. There have been various well-known benchmark apps available for download from mobile application stores to measure both the system-level performance of device, such as AnTuTu [2], Basemark OS II [3], and specialized components, such as 3DMark and GFXBench for graphic features [1, 16], Geekbench for processors [15] and Browsermark for browsers [3]. We decide to choose Basemark OS II (referred only as Basemark hereafter for the sake of brevity) as the exemplary benchmark tool in this study for the following reasons: First, it is supported by all three leading popular mobile platforms, including Android, iOS and Windows Phone. Second, it tests different technical features of the device and produces an objective overall score. Third, it closely cooperates with numerous major players in embedded industry that ensures its wide acceptance2 . In summary, Basemark allows easy comparison of the overall device performance for almost all smartphone models across mobile platforms. Figure 2 shows the user interface and benchmark result obtained from a free version of its mobile app that runs on Samsung Galaxy S6. – Fragmentation performance test is similar to variable file size performance test, but measures transfer rate inside a fragmented memory scenario. • Graphics tests – Shader effect test displays several 2D/3D graphics inside the same scene and measures the GPU pixel processing speed. – Rendering effect tests display 100 particles with one draw calls and renders the scene to a full highdefinition resolution offscreen buffer 100 times before being drawn onto the screen to measure GPU vertex operations. • Web browsing tests – CSS 3D rendering test is based on several CSS3 3D transformations and measures number of objects transformed. Transform functions use a quasirandom number as an argument. – HTML5 canvas test creates HTML graphic objects to measure rendering performance. – CSS resize test emulates screen size change (e.g. when orientation changes) by resizing multiple objects inside one master container. Figure 2: User interface and benchmark results obtained from Basemark OS II installed on Samsung Galaxy S6. Basemark features a comprehensive suite of tests in four groups, including system, memory, graphics and web browsing. Admittedly other benchmark tools may include different tests; we believe tests used by Basemark are representative to capture important system-level performance. We list the detailed score breakdown from each aspect below: • System tests – Math test measures the CPU processing speed of integers and floating points operations. – XML parsing test measures the CPU utilization of parsing XML files. – CPU single core test measures how fast a single CPU core can perform image processing in 2048x2048 pixels, 32-bit image. – CPU multi core test measures how fast all the CPU cores together can perform image processing in 2048x2048 pixels, 32-bit image. • Memory tests – Fixed file size performance test measures the reading/writing transfer rate (MB/s) to load/create files in the internal device storage. – Variable file size performance test measures the reading/writing transfer rate (MB/s) to load/create files in the internal device storage. 2 Basemark initiates a Benchmark Development Program with members from smartphone industry including AMD, ARM, Broadcom, Digital Media Professionals, Imagination Technologies, Intel, Marvell, MediaTek, Microsoft, Nvidia, Renesas, Samsung, Qualcomm and Xiaomi. Essentially, each group of tests produces a group score (SGi , i = 1, 2, 3, 4) and then Overall Score (SO) is calcuQ lated as: SO = ( 4i=1 SGi )1/4 . This reflects that overall system-level performance can be thought of as being multiplicative in the performance of each aspect [9] and as being proportional for comparison to other smartphone models. 4. DATA We implement a web crawler and collect detailed information about full technical specifications of smartphone models launched between July 2012 and July 2015 from GSM Arena [20]. GSM Arena is an independent website that compiles mobile device information from manufacturers and conducts editorial reviews on popular models since 2000. Our decision to use GSM Arena for obtaining smartphone features is consistent with prior studies that collect phone specifications during the years 1992-2002 [26] and between January 2004 and August 2012 [8] from the same source. We remove feature phones (models without mobile OS) and tablets (models without cellular connectivity and screen size is larger than 7 inches) from the crawled data and the resulting dataset contains 1,743 smartphone models released by 62 vendors. As smartphones are expected to continuously improve over time, we follow the standard in the industry to organize the smartphones based on the quarterly launched date. Figure 3 shows the number of new models based on mobile OS from 2012Q3 to 2015Q3. We find that the Android clearly is the dominant mobile OS that 57 smartphone vendors choose to build their products due to its relative openness, whereas Apple builds the own proprietary mobile platform and only launches products once a year. This indicates that for most of the smartphone vendors, they need to invest in the development of technical features that help differentiate their products once the mobile OS is commodified [31]. Table 1 shows relevant technical features in the dataset. Among all of the technical features, ones marked in italic have been used in over 95% of smartphone models, implying these features have become standard functionality that smartphone vendors must include in their product design strategies even before our study period. Thus we leave these features out and alternatively focus on technical feature dynamics that still undergo considerable improvement in the next section. 5. Figure 3: Number of new smartphone models by mobile OS from 2012Q3 to 2015Q3 We intend to explain the evolution of technical features used in smartphone models mainly from three aspects. First, we look at categorical features that either add new functionality or jump to the next level through the percentage of smartphones including each of these features (Fig. 4a-c). Second, we discuss continuous features that keep evolving over time through the averaged value of each of these features (Fig. 4d-f). Third, we introduce the benchmark score to describe the system-level performance of each smartphone, such that the evolution of multidimensional technical features described in the first two aspects can be easily understood using just a single index value. 5.1 Table 1: Extracted smartphone features list Feature Type Feature Brand; launch date (quarter); price Main group3 Physical display size (inches); resolution Display (pixel-per-inch); multi-touch screen 4G LTE; Wi-Fi Network Dimensions, weight; SIM type Body (mini/micro/nano) Primary camera resolution (mega-pixels); Camera secondary camera Manufacturer; multi-core (dual/quad Chipset /octa) RAM size; internal memory size Memory 3.5mm audio jack ; loudspeaker Sound Bluetooth; infrared port; NFC; miCommunication croUSB ; radio; GPS Capacity (mAh) Battery Benchmark score Performance TECHNICAL FEATURE DYNAMICS Categorical Features Fig. 4a demonstrates the extent of several key service enabling features to be diffused among the launched smartphone models during the period of study. Smartphone vendors increasingly build the phone models to support 4G networks as the infrastructure becomes more widespread. More specifically, the percentage of smartphone models that support 4G network increases from 20% to over 50% in contrast to the findings by Cecere et al. (2015) that only 6% of smartphone models do so before 2012Q3 [8]. Meanwhile, the secondary camera gains even more popularity, indicating that dual-camera becomes the dominant design that smartphone vendors can only add extra value through improving the camera resolution. We also observe the increased use of smaller-sized SIM card (in terms of both Micro-SIM and Nano-SIM) over time, whereas the diffusion of NFC and infrared sensor still remains low. We demonstrate the substitution of internal memory and storage as shown in Fig 4b. As larger internal memory allows faster multi-task processing, 2GB RAM is gradually growing in use and nearly catch up with the 1GB RAM. Also, we see clear substitution between 8GB and 16GB storage and 4GB storage, which reflect the demand for larger storage space for increased smartphone usage. However, the 32GB storage has not widely diffused, indicating that the demand for larger physical storage cannot justify the extra cost yet. As multi-core CPUs generally boost the performance at more efficient energy consumption, smartphone vendors tend to choose carefully the chipset that embeds with the more powerful CPU. From Fig 4c we find that the quad-core CPU has quickly replaced the dual-core CPU as the standard configuration of the chipset during the studied period. We also notice the emergence of octa-core CPU and expect it to surpass the dual-core CPU soon. 5.2 3 Continuous Features The price group represents the price in a scale of 1-9 for the comparison reference because smartphone price may change dynamically and differ from countries. (a) (b) (c) (d) (e) (f) Figure 4: Evolution of technical characteristics for smartphone models launched between 2012Q3 and 2015Q3: (a) 4G LTE and accessories; (b) Internal storage and RAM; (c) Multi-core CPU; (d) Average height and weight; (e) Display screen size and resolution; (f ) Camera resolution and battery capacity We evaluate the physical design of smartphones from two aspects. The body dimension of mobile handsets has experienced substantial changes during the feature phone era, i.e., the phone becomes smaller and lighter [27]. Interestingly, we observe that both the size and weight of smartphone models has increased during the studied period (Fig. 4d). In particular, the development of physical display makes the average size of touch screen increase from 4 inches to nearly 5 inches and average screen resolution is approaching 300 pixels per inch, the industry standard beyond which the human eye can hardly recognize the difference (Fig. 4e). This is consistent with findings from [8] that smartphone vendors compete in the horizontal innovations such as physical design to differentiate the products. This results in the emergence of smartphones with ever-larger screen (commonly known as phablets), as the boundary between smartphone and tablet is less clear. Lastly, we show the technological evolution of camera and battery embedded in the smartphone in terms of camera resolution and battery capacity, respectively (Fig 4f). The average camera resolution has increased from 6 mega-pixels to 9 mega-pixels, and the average battery capacity has increased by over 500 mAh. Thus the improvement of the listed two technical characteristics would be very important to yield better image quality and longer battery life. 5.3 Benchmark Performance As explained earlier, we use the Basemark benchmark scores provided by GSM Arena instead of other sources (e.g. smartphone vendors) to represent the performance of each smartphone model, because the website performs an independent editorial review that helps us to avoid the so-called “bench-marketing” issue. However, as GSM Arena reviews a subset of popular smartphone models since 2013Q3, we only retain 142 models with the benchmark score released by 22 smartphone vendors for our analysis. We note that despite the limited size of this benchmark dataset, it features almost all leading smartphone models across popular mobile platforms from major vendors. Therefore, we believe the dataset should suffice our needs to characterize the device performance. We first account for the smartphone performance by mobile platform (Android, iOS and Windows Phone) over time in Fig. 5a. We clearly identify that Apple and other Androidbased vendors have different product design strategies. More specifically, although iPhone is launched once each year, it outperforms other contemporaneous competing models and maintains high performance except for 2013Q3 that Apple released low cost iPhone 5c, which may help explain its market success. In contrast, Android-based smartphones cover a very wide range of performance from high-end models to compete with Apple (e.g. Samsung Galaxy S series) to lowend models that aim at developing country market. Windows phones tend to have relatively lower performance compared to other competing models, which may help explain its limited market share. Moreover, we examine smartphone performance by price range in Fig. 5b. More specifically, based on the price group information we categorize smartphones into low-end ([1:3]), mid-end ([4:6]) and high-end ([7:9]) models. We show that the device performance smartphone models can be very indicative of the market segment they belong to, i.e. the highend smartphone models tend to have higher performance than mid-end smartphone models, which in turn are better than low-end smartphone models. This implies that the benchmark performances may help proxy the relative quality of the smartphones without including a large variety of technical features. Our findings also reveal product pricing strategies that may be insightful for understanding the competitive landscape of smartphone marketplace. For example, Chinese vendor Xiaomi follows aggressive strategy by launching ”monster performance” models with the much lower price than competing models that have comparable performance. 6. DISCUSSIONS AND FUTURE RESEARCH Through analysis of technical features incorporated into the smartphone models, we have the following findings on recent industrial dynamics in the smartphone industry. First, novel categorical features are in different stages of diffusion, implying that smartphone vendors might choose to retrofit certain features to smartphone models in response to market demand. For example, the need for taking selfportrait photos popularizes smartphones equipped with secondary cameras. Second, core hardware components, such as CPU, RAM and storage still undergo significant improvement to support faster processing power, as more computing resources are required for the increasing usage of sophisticated mobile apps. Third, smartphone screens have become larger with a better resolution due to the advances in display technology. Fourth, more battery capacity may help to ensure steady battery life given the growing power consumption. Fifth, performance benchmarks further provide us with a holistic view of the technological evolution of smartphones. More specifically, smartphone models designed for different end-user market segments exhibit distinct performance. During each quarter, high-end smartphones built at the technological edge tend to achieve better performance over those launched previously. Therefore, the smartphone industry is largely innovative and continues to evolve over time, although certain features have emerged as the standard functionality. Our use of benchmark may not only help capture the overall device performance, but also shed some light on future research. As benchmark has been widely used to measure the quality changes of high technology products with rich technical characteristics in constructing the hedonic price index, it may also be adapted to adjust the quality of smartphones in hedonic regression for its even more complex synergies between technical features [9, 10]. Moreover, benchmark allows customers to easily grasp the smartphone performance and compare across models without having to comprehend all technical specification details. Thus learning how objective benchmark score is linked with the user evaluation of smartphone performance would be important to understand perceived value and customer satisfaction (e.g. [36]). Lastly, we believe that the benchmark can be generalized to study the performance of other smart devices, such as tablets, wearable accessories, etc. in a similar fashion. 7. REFERENCES [1] 3DMark. http://www.futuremark.com/benchmarks/3dmark. [2] AnTuTu Benchmark. http://www.antutu.com/en/index.shtml. [3] Basemark OS II Benchmark. http://www.basemark. com/product-catalog/basemark-os-ii. [4] C. Benkard and P. Bajari. Hedonic price indexes with unobserved product characteristics, and application to personal computers. Journal of Business and Economic Statistics, 23(1):61–75, 2005. [5] E. Berndt and Z. Griliches. Price indexes for microcomputers: An explorative study. NBER Working Paper No. 3378, 1990. [6] D. Byrne, S. Oliner, and D. Sichel. How fast are semiconductor prices falling? NBER Working Paper No. 21074, 2015. [7] M. Campbell-Kelly, D. Garcia-Swartz, R. Lam, and Y. Yang. Economic and business perspectives on smartphones as multi-sided platforms. Telecommunications Policy, 39(8):717–734, 2015. [8] G. Cecere, N. Corrocher, and R. D. Battaglia. Innovation and competition in the smartphone industry: Is there a dominant design? Telecommunications Policy, 39(3-4):162–175, 2015. [9] P. Chwelos. Approaches to performance measurement in hedonic analysis: Price indexes for laptop computers in the 1990s. Economics of Innovation and New Technology, 12(3):199–224, 2003. [10] P. Chwelos, E. Berndt, and I. Cockburn. Faster, smaller, cheaper: An hedonic price analysis of PDAs. Applied Economics, 40(22):2839–2856, 2008. [11] L. Einav, J. Levin, I. Popov, and N. Sundaresan. Growth, adoption and use of mobile e-commerce. American Economic Review: Papers & Proceedings, 104(5):489–494, 2014. [12] D. Garcia-Swartz and F. Garcia-Vicente. Network effects on the iPhone platform: An empirical examination. Telecommunications Policy, 39(10):877–895, 2015. (a) (b) Figure 5: Benchmark score to represent device performance of smartphone models between 2013Q3 and 2015Q3: (a) by mobile platforms; (b) by price range. [13] Gartner. www.gartner.com/newsroom/id/3187134, 2016. [14] A. Gawer and M. Cusumano. Industry platforms and ecosystem innovations. Journal of Product Innovation Management, 31(3):417–433, 2014. [15] Geekbench 3. http://www.primatelabs.com/geekbench. [16] GFXBench. https://gfxbench.com/benchmark.jsp. [17] A. Ghose and S. Han. Estimating demand for mobile applications in the new economy. Management Science, 60(6):1470–1488, 2014. [18] R. Goettler and B. Gordon. Does AMD spur Intel to innovate more? Journal of Political Economy, 119(6):1141–1200, 2011. [19] B. Gordon. A dynamic model of consumer replacement cycles in the PC processor industry. Marketing Science, 28(5):846–867, 2009. [20] GSM Arena. http://www.gsmarena.com. [21] S. Han, S. Park, and W. Oh. Mobile app analytics: A multiple discrete-continuous choice framework. MIS Quarterly, Forthcoming, 2015. [22] H. Hoehle and V. Venkatesh. Mobile applications usability: Conceptualization and instrument development. MIS Quarterly, 39(2):435–472, 2015. [23] T. Islam and N. Meade. The diffusion of successive generations of a technology: A more general model. Technological Forecasting and Social Change, 56(1):49–60, 1997. [24] M. Kenney and B. Pon. Structuring the smartphone industry: Is the mobile Internet OS platforms the key? Journal of Industry, Competition and Trade, 11(3):239–261, 2011. [25] A. Kivi, T. Smura, and J. Toyli. Technology product evolution and the diffusion of new product features. Technological Forecasting and Social Change, 79(1):107–126, 2012. [26] H. Koski and T. Kretschmer. Innovation and dominant design in mobile telephony. Industry and Innovation, 14(3):305–324, 2007. [27] H. Koski and T. Kretschmer. New product development and firm value in mobile handset [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] production. Information Economics and Policy, 22(1):42–50, 2010. D. Ladd, A. Datta, S. Sarker, and Y. Yu. Trends in mobile computing within the IS discipline: A ten-year retrospective. Communications of the Association for Information Systems, 27(Article 17), 2010. M. Niculescu and S. Whang. Codiffusion of wireless voice and data services: An empirical analysis of the Japanese mobile telecommunication market. Information System Research, 23(1):260–279, 2012. C. Nosko. Competition and quality choice in the CPU market. Working paper, University of Chicago, 2015. B. Pon, T. Seppala, and M. Kenney. Android and the demise of operating system-based power: Firm strategy and platform control in the post-PC world. Telecommunications Policy, 38(11):979–991, 2014. B. Pon, T. Seppala, and M. Kenney. One ring to unite them all: Convergence, the smartphone, and the cloud. Journal of Industry, Competition and Trade, 15(1):21–33, 2015. A. Rennhoff and P. Routon. Can you hear me now? the rise of smartphones and their welfare effects. Telecommunications Policy, 40(1):39–51, 2016. A. Riikonen, T. Smura, A. Kivi, and J. Toyli. Diffusion of mobile handset features: Analysis of turning points and stages. Telecommunications Policy, 37(6-7):563–572, 2013. A. Riikonen, T. Smura, A. Kivi, and J. Toyli. The effects of price, popularity, and technological sophistication on mobile handset replacement and unit lifetime. Technological Forecasting and Social Change, 103:313–323, 2016. D. Shin. Effect of the customer experience on satisfaction with smartphones: Assessing smartphone index with partial least squares. Telecommunications Policy, 39(8):627–641, 2015. J. West and M. Mace. Browsing as the killer app: Explaining the rapid success of Apple’s iPhone. Telecommunications Policy, 34(5-6):270–286, 2010. Y. Yoo, R. Boland, K. Lyytinen, and A. Majchrzak. Organizing for innovation in the digitized world. Organization Science, 23(5):1398–1408, 2012.