The use of applications on mobile devices has changed dramatically over the past few years. While web browsing was once a common activity, it's now reported that 86% of time on mobile phones is in apps other than the browser. We set out to understand how the mobile web was currently fitting into people's lives and what web sessions looked like. Finding a dramatic reduction in mobile web revisi-tation rates compared to previous work and that a large number of sessions comprised single page views, we then studied how web content was shared with others in mobile messaging, the source of many single page sessions. The HCI community has not heavily studied this sharing activity that many people perform daily. We conclude with design implications for new mobile applications from our two studies with a combined 287 participants where we studied actual logs of mobile web use and link sharing behavior.

When trying to satisfy an information need, smartphone users frequently transition from mobile search engines to mobile apps and vice versa. However, little is known about the nature of these transitions nor how mobile search and mobile apps interact. We report on a 2-week, mixed-method study involving 18 Android users, where we collected real-world mobile search and mobile app usage data alongside subjective insights on why certain interactions between apps and mobile search occur. Our results show that when people engage with mobile search they tend to interact with more mobile apps and for longer durations. We found that certain categories of apps are used more intensely alongside mobile search. Furthermore we found differences in app usage before and after mobile search and show how mobile app interactions can both prompt mobile search and enable users to take action. We conclude with a discussion on what these patterns mean for mobile search and how we might design mobile search experiences that take these app interactions into account.

Driven by curiosity and our own three diverse smartphone application usage datasets, we sought to unpack the nuances of mobile device use by revisiting two recent Mobile HCI studies [1, 17]. Our goal was to add to our broader understanding of smartphone usage by investigating if differences in mobile device usage occurred not only across our three datasets, but also in relation to prior work. We found differences in the top-10 apps in each dataset, in the durations and types of interactions as well as in micro-usage patterns. However, it proved very challenging to attribute such differences to a specific factor or set of factors: was it the time frame in which the studies were executed? The recruitment procedure? The experimental method? Using our somewhat troubled analysis, we discuss the challenges and issues of conducting mobile research of this nature and reflect on caveats related to the replicability and generalizability of such work.

Notifications on mobile phones alert users about new messages, emails, social network updates, and other events. However, little is understood about the nature and effect of such notifications on the daily lives of mobile users. We report from a one-week, in-situ study involving 15 mobile phones users, where we collected real-world notifications through a smartphone logging application alongside subjective perceptions of those notifications through an online diary. We found that our participants had to deal with 63.5 notifications on average per day, mostly from messengers and email. Whether the phone is in silent mode or not, notifications were typically viewed within minutes. Social pressure in personal communication was amongst the main reasons given. While an increasing number of notifications was associated with an increase in negative emotions, receiving more messages and social network updates also made our participants feel more connected with others. Our findings imply that avoiding interruptions from notifications may be viable for professional communication, while in personal communication, approaches should focus on managing expectations.

The goal of this work is to provide a fundamental understanding of the daily information needs of people through a large-scale, in-depth, quantitative investigation. To this end, we have conducted one of the most comprehensive studies of information needs to date, spanning a 3-month period and involving more than 100 users. The study employed a contextual experience sampling method, a snippet-based diary technique using SMS technology, and an online Web diary to gather in situ insights into the types of needs that occur from day to day, how those needs are addressed, and how contextual, technological, and demographic factors impact on those needs. Our results not only complement earlier studies but also provide a new understanding of the intricacies of people’s daily information needs.

With the advent of instant mobile messaging applications, traditional SMS is in danger of loosing it's reign as the king of mobile messaging. Applications like WhatsApp allow mobile users to send real-time text messages to individuals or groups of friends at no cost. While there is a vast body of research on traditional text messaging practices, little is understood about how and why people have adopted and appropriated instant mobile messaging applications. The goal of this work is to provide a deeper understanding of the motives and perceptions of a popular mobile messaging application called WhatsApp and to learn more about what this service offers above and beyond traditional SMS. To this end, we present insights from two studies an interview study and a large-scale survey highlighting that while WhatsApp offers benefits such as cost, sense of community and immediacy, SMS is still considered a more reliable, privacy preserving technology for mobile communication.

The explosive growth of the mobile application (app) market has made it difficult for users to find the most interesting and relevant apps from the hundreds of thousands that exist today. Context is key in the mobile space and so too are proactive services that ease user input and facilitate effective interaction. We believe that to enable truly novel mobile app recommendation and discovery, we need to support real context-aware recommendation that utilizes the diverse range of implicit mobile data available in a fast and scalable manner. In this paper we introduce the Djinn model, a novel context-aware collaborative filtering algorithm for implicit feedback data that is based on tensor factorization. We evaluate our approach using a dataset from an Android mobile app recommendation service called appazaar. Our results show that our approach compares favorably with state-of-the-art collaborative filtering methods.

Recent work in mobile computing has highlighted that conversations and social interactions have a significant impact on mobile Web and mobile search behaviours. To date, however, this social element has not been explored fully and little is known about why and how mobile users search for information in social settings. The goal of this work is to provide a deeper understanding of social mobile search behaviours so that we may improve future mobile search experiences that involve a social component. To this end we present the results of two studies: a survey involving almost 200 users and a two-week diary and follow-up interview study of 20 users. Our results extend past research in the mobile search space, by exploring the motivations, circumstances and experiences of using mobile search in social settings to satisfy group information needs. Our findings point to a number of open research challenges and implications for enriching the search experiences of mobile users.

Mobile, local recommendations are on the rise. Surprisingly however, research addressing user perceptions of local recommendations and local differences when interacting with such recommendation services is yet scarce. Location-based recommendation services are mostly evaluated from a `recommendation systems' standpoint, with limited experiential insights from users and limited focus on local differences that may apply. This workshop focuses on the local, personal user experience, and provides a forum to exchange experiences, insights and strategies in personalizing local mobile applications and generating local recommendations that fit local user needs.

The term mobile Web is changing. Mobile is traditionally associated with on-the-move, portable and dynamic. However, with the advent of smartphones, an increasing number of users are accessing the mobile Internet via their phone while in more stationary and familiar settings, like at home or at work. This shift in the meaning of mobile is having a significant effect on mobile Web behavior. Designing great mobile Web experiences requires a deeper understanding of the information needs, behaviors and underlying motivations of mobile users. As such, the goal of this work is to study this shift and its impact on mobile Internet access, with a view to determining what this means for the future of the mobile Web and in particular mobile search. In this paper we present the results of an online diary and interview study of 18 active mobile Web users over a 4-week period focusing on how, why, where and in what situations people use the mobile Internet and mobile search. Our findings raise a new set of open research questions and point to a number of implications for enriching the experiences of mobile Web users.

The mobile Internet offers anytime, anywhere access to a wealth of information to billions of users across the globe. However, the mobile Internet represents a challenging information access platform due to the inherent limitations of mobile environments, limitations that go beyond simple screen size and network issues. Mobile users often have information needs which are impacted by contexts such as location and time. Furthermore, human beings are social creatures that often seek out new strategies for sharing knowledge and information in mobile settings. To investigate the social aspect of mobile search, we have developed SocialSearchBrowser (SSB), a novel proof-of-concept interface that incorporates social networking capabilities with key mobile contexts to improve the search and information discovery experience of mobile users. In this paper, we present the results of an exploratory field study of SSB and outline key implications for the design of next generation mobile information access services.

The mobile space is evolving at an astonishing rate with over 4.1 billion subscribers in existence. The world is also witnessing an explosion in social web services with more users seeking novel ways of interacting with friends and family. We are interested in the combination of these two exciting research spaces: the social web and the mobile web. We believe that the social mobile web is going to be a highly influential research area in the near future and given the huge growth that both these fields have experienced in recent times we feel that now is an excellent time to discuss this nascent research space. This workshop continues the successful social mobile web workshop held as part of SocialCom in 2009. The workshop explores the current state of the social mobile web and combines technical presentations, demos and position papers to drive interaction and discussion among participants.

As the mobile Internet continues to grow, there is an increasing need to provide users with effective search and information access services. In order to build more effective mobile search services, we must first understand the impact that various interface choices have on mobile users. For example, the majority of mobile location-based search services are built on top of a map visualization, but is this intuitive design-decision the optimal interface choice from a human centric perspective? In order to tackle this fundamental design question, we have developed two proactive mobile search interfaces (one map-based and the other text-based) that utilize key mobile contexts to improve the search and information discovery experience of mobile users. In this paper, we present the results of an exploratory field study of these two interfaces - involving 34 users over a 1 month period - where we focus in particular on the impact that the type of user interface (e.g. map vs text) has on the search and information discovery experience of mobile users. We highlight the main usage results - including that maps are not the interface of choice for certain information access tasks - and outline key implications for the design of next generation mobile search services.

Mobile phones are becoming increasingly popular as a means of information access while on-the-go. Mobile users are likely to be interested in locating different types of content. However, the mobile space presents a number of key challenges, many of which go beyond issues with device characteristics such as screen-size and input capabilities. In particular, changing contexts such as location, time, activity and social interactions are likely to impact on the types of information needs that arise. In order to offer personalized, effective mobile services we need to understand mobile users in more detail. Thus we carried out a four-week diary study of mobile information needs, looking in particular at the goal/intent behind mobile information needs, the topics users are interested in and the impact of mobile contexts such as location and time on user needs.

Mobile devices and the mobile Internet represent an extremely challenging search environment. Limited screenspace, restricted text-input and interactivity, and impatient users all conspire to exacerbate the shortcomings of modern Web search. Recently researchers have proposed that typically vague search queries be augmented by context information, as a way to help search engines to retrieve more relevant information. In this paper we propose a novel interface to support multi-dimensional, context-sensitive mobile search, combining context features such as location, time, and community preferences to offer a unique search experience that is well-adapted to the needs of mobile users.

In this paper we describe the results of a four-week diary study of mobile information needs, focusing on the intent behind mobile needs and the importance on context on such needs. We identified three key intents among diary entries: informational, geographical and personal information management (PIM). Furthermore, we found many of these information needs have high temporal and location dependencies.

Recent evidence suggests that mobile search is becoming an increasingly important way for mobile users to gain access to online information, especially as off-portal content continues to grow rapidly. In this paper we study the characteristics of mobile search by analysing approximately 6 million individual search requests generated by over 260,000 individual mobile searchers over a 7-day period during 2006. We analyse the patterns of queries used by mobile searchers and focus on key characteristics such as the clickthru rates of mobile searches in order to understand, for the first time, just how well mobile search engines are responding to user queries. Moreover, we compare our results to a number of recent mobile studies and highlight some of the key differences between mobile search and traditional Web search behaviours.

Delivering an effective mobile search service is challenging for many reasons. Certainly small-screen mobile handsets with limited text input capabilities do not make ideal search devices. In addition, the brevity of Mobile Internet content hampers effective indexing and limits retrieval opportunities. In this paper we focus on this indexing issue and describe an approach that leverages Web search engines as a source of content enrichment. We present an evaluation using a mobile news service that demonstrated significant improvements in search performance compared to a standard benchmark sys-tem.

It is likely that mobile phones will soon come to rival more traditional devices as the primary platform for information access. Consequently, it is important to understand the emerging information access behavior of mobile Internet (MI) users especially in relation to their use of mobile handsets for information browsing and query-based search. In this article, we describe the results of a recent analysis of the MI habits of more than 600,000 European MI users, with a particular emphasis on the emerging interest in mobile search. We consider a range of factors including whether there are key differences between browsing and search behavior on the MI compared to the Web. We highlight how browsing continues to dominate mobile information access, but go on to show how search is becoming an increasingly popular information access alternative especially in relation to certain types of mobile handsets and information needs. Moreover, we show that sessions involving search tend to be longer and more data-rich than those that do not involve search. We also look at the type of queries used during mobile search and the way that these queries tend to be modified during the course of a mobile search session. Finally we examine the overlap among mobile search queries and the different topics mobile users are interested in.