With mobile phones and devices, online social networks, and internet, we can connect our offline activities and experiences and share them online easily. Sensors in our phones and mobile devices collect context in order to record the activities that we do and the people that we meet. We can truly now do mobile social networking, that is, connect with people to create social networks directly through the phone, rather than connect to people indirectly by adding them on social networks on the phone, which we call social networking on mobile.
Online social networking did not really truly become ubiquitous to the public and explode until Facebook ( http://www.facebook.com ) came along. People could easily communicate their thoughts and share them with others using blogs and social networking sites such as Facebook, Friendster, and MySpace ( http://www.myspace. com ). Facebook started to create the Status page, where people could announce what they were doing and share that with others, and see the Feed of updates of all the friends, thus creating the ‘stickiness’ and community experience that to many serves as an addiction. In 2006, Twitter ( http://www.twitter.com ) was born, which even simplified the broadcasting of content by introducing the microblogging concept of posting an update (called a tweet) within 140 characters. This made it even easier to quickly post updates to friends and to the public, and this started to create
real-time data streams and made possible much research on the user behavior, social influence, and spreading of information in Twitter
With the ubiquity of the mobile phone being used to take pictures and with GPS available in nearly all phones now, Foursquare ( http://www.foursquare.com ) was born in 2009. This enabled location-based social networking where people can check in at a location and share their status and photos with others (called social location sharing), which helps to bridge the gap between offline and online. Nonetheless, it is the phone that helps to connect people together in a mobile social network, whether it is by phone call, SMS, or an online social networking application. With Wi-Fi and 3G wireless technologies everywhere, the bandwidth is large enough to allow for an always-on connection, and since nearly everyone now has a mobile phone, online social networking and communication has never been so easy.
Social media and social networking technologies such as Facebook, Foursquare, Instagram (http://www.instagram.com ), WhatsApp ( http://www.whatsapp.com ) andPath ( http://www.path.com ) connect the offline from the capturing of photos in the real world and the location from GPS and Wi-Fi, to the online social networking world of Facebook and Twitter. However, social networking technologies on the mobile phone are considered as social networking on mobile because people can still do social networking on other devices such as PCs and laptops. The mobile device, such as a mobile phone, captures context which includes location and accelerometer, so it is more than just accessing a social network through an application that connects to the Internet. It is about recording context and then connecting people through the common physical context, such as co-location, co-encounter, and co-activity. We are now beginning to see serendipity applications such as Glancee
( http://www.glancee.com ) which was acquired by Facebook, Highlight ( http://
http://www.highlig.ht.com ), and Banjo ( http://ban.jo ), which are social discovery applications that help you discover friends and strangers near you offline then connect to them online, or notify you if you have any online friends near you.
We believe that mobile social networking does not only encompass accessing online social networks from the mobile, but also connecting the offline to online and vice versa via the mobile. In other words, our definition of mobile social networking is as follows. Mobile social networking makes the mobile become an integral part of your social network and lifestyle. It combines distributed content sharing, social networks, sensor networks, and pervasive computing together on the phone in order to provide an integrated experience that fuses physical and digital social interactions through the mobile. An example can illustrate how mobile social networking can help to make your daily life easier, such as providing you an automatic reminder to complete a task, which we call a social reminder. Let’s say that you see someone in an elevator that looks familiar. Your phone can display information
to inform you who is that person (based on your previous meetings and encounters as recorded by the sensor and social networks), then you know how to greet that person. The system will automatically exchange business cards seeing that you do not have that person’s contact in your phone, using pervasive computing technologies. When you get off the elevator, the phone will recognize that your manager is
behind you and send you a social reminder that you need to send a sales report to him at the end of the day (after looking at your calendar and your e-mail from your manager).
So what differentiates a mobile social network from social network on mobile?
First, when people meet each other, the duration that they meet and social network with each other has a definitive start and end time, which lasts for a temporary period of time before they leave and depart their separate ways. We call this duration of networking ephemeral, as opposed to continuous where the duration of networking has no specifi c start and end time. Social networking on mobile such as accessing Facebook on your mobile phone has a continuous duration of networking; there is no actual start and end time for the social interactions. Facebook has the Timeline which indicate events during which you and others were apparently doing things together; however, it does not record offline interactions directly. Second, people usually meet each other at events or activities, therefore the offline interactions are within the activity. Think about the last time you met someone and socially networked with them; it was probably at some type of event or activity. However, these interactions are not recorded automatically (at least, they can be recorded, but manually through check-in or posting a status indicating the activity that the two of you were doing together). Third, the granularity of proximity and location is different between social networking on mobile and mobile social networking. With social networking on mobile, the granularity of location is by co-location, i.e., you and someone else are at the same place since the location technology used is usually GPS. Co-location is used by social networking applications such as Foursquare to indicate if you are in the same place as another person, and allows you to check in. On the other hand, with mobile social networking, since the mobile can use Bluetooth, Wi-Fi, or NFC, these wireless technologies can be used to detect other mobiles nearby, or can detect whether two people encountered each other.
Fourth, with many sensors that are provided on a mobile phone such as the accelerometer, mobile phones can be used to capture various elements of context. Activity can be inferred from the mobile context which means that in conjunction with proximity and location, it can be used for detecting social interactions for mobile social networking. Fifth, most social networking applications on mobile allow you to discover contacts indirectly, i.e., you have to manually find the contact you are looking for through searching on the social network (as for example in Facebook) for adding contacts. This is very
cumbersome, especially if there is more than one person with the same name. However, this problem does not exist with mobile social networking, because through proximity technologies you can find who the person is close to you (within reasonable accuracy depending on the proximity technology), therefore you can easily add a contact directly through your encounter. For example, Find & Connect
is a system where you can directly add a contact around you from your mobile phone. Sixth, because of the proximity and groups that are formed from the mobile social network, privacy can be finely grained into categories of public, group, and private, with group privacy being specified from the people who were together at the activity. In social networking on mobile, the default for privacy is public, since most people fi nd it cumbersome to specify who they wish to post to and share the message with. Finally, to collaborate with someone using social networking applications on your mobile, you need to coordinate with the person you want to collaborate by sending a message or notifying them. That means a setup time is required to add the person to your social network, before you can start collaborating. For example, in WhatsApp, if you want to set up a group to discuss organizing an event, first you have to fi nd the people in the group in WhatsApp and then send a friend request (if they are not added as your friends already). Second, once they are friends, then you have to create a group and manually invite each
friend to the group, and each friend has to accept the invitation. However, with mobile social networking, the collaboration is ad hoc because it records the people who you were with together in the group, which means that there is no need to manually add people to the online group.
We can see that mobile social networking presents the next generation of social networking that really does bridge the gap between offline and online.