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Hacking Online Applications for Location Awareness

by Christopher Ngan

Throughout the last decade, online applications have incorporated models of real-world interactions in order to build increasingly useful online services. From Amazon's early use of collaborative filtering to pure social networking applications based on user collaboration and sharing, the online experience is clearly better for its increasing approximation of real-world interactions. In spite of the virtual world realizing increased value by copying lessons from the real world, the real-world experience has not yet realized an equivalent level of usability; nor has it benefited from advances made in the online world.

With the advent of a new ad hoc, wireless mesh networking technology designed to support peer-to-peer connectivity in highly mobile networks, the final barrier to location-aware services has been hurdled, allowing a level of network connectivity previously available only in the wire-line internet.

Open source solutions are lowering the cost of rolling out applications. Jabber and XMPP, Asterisk and VXML, and VLC: all industrial-strength open source projects and protocols that can be molded by individual hackers and large companies alike to build a seemingly limitless number of location-aware services. With the cost effectiveness and quality of open source projects and the presence of a new distributed peer-to-peer wireless network technology, the tools are in place for bringing the richness of online applications to the offline world. Furthermore, the location-aware services possible are ideal for brick-and-mortar retailers and service providers offering up a variety of business models crucial to ensuring long-term viability.

With both the core infrastructure and application-level tools so accessible, grassroots hacking and development can result in the use of existing applications modified for location awareness. While the core applications remain similar, their use in a different environment will result in unique standalone uses and novel mashups of text/chat, voice, and video services.

Hacking Chat and IM for Location Awareness

O'Reilly Emerging Telephony Conference 2006

Within the realm of text/chat, typical IM applications can be easily hacked to offer peer-to-peer connectivity that, while nonsensical in the virtual world, becomes highly valuable in the real world. Decentralizing the typical IM infrastructure is trivial, yet doing so enables a new class of location-aware IM and chat functionality that presages the voice and video applications that will be built.

Hacking Voice for Location Awareness

Within the realm of voice, many of the same principles apply, but with the increased interactivity and richness of voice. The ability to route IP calls on to and off from the PSTN network through the use of Asterisk further improves the backwards-compatibility of next-generation, location-aware voice services built on VXML and other open protocols. Some of the applications that can be built include:

Hacking Video for Location Awareness

Finally, the realm of video is one in which true video interactivity will likely be limited in the near future until wireless technologies increase effective bandwidth. However, it's possible for half-duplex video services such as on-demand video to be deployed in select wireless mesh networks. Through the use of VLC, an example of a location-aware video applications that can be built today includes:

Integration of Text/Chat, Voice, and Video Location-Aware Services

In conjunction with a personal profile, or even a tag cloud generated from a user's online blog or RSS subscriptions, the end user's exposure to text/chat, voice, and video interactions can be filtered and customized. Text/chat, voice, and video data can be tagged, either explicitly or implicitly, through simple frequency and sentence-structure analysis or more involved algorithms. At increasing levels of customization, variable pricing based on variables such as customers' profiles, retailer inventory, and retailer delivery schedules can also be offered to improve sales efficiency.


Fundamentally, the technologies exist to offer location-based services that can effectively extend the reach of retailers while simultaneously encouraging a greater level of interpersonal interaction. With the proliferation of these predominately push-based technologies, a need for filtering mechanisms is necessary for realistic navigation of information. As with other online technologies, though, convenience of personalization must be balanced against privacy, a particularly important concern in geographically based services.

Want to Learn More?

Join us at our two Bird of a Feather sessions at the O'Reilly Emerging Telephony conference, January 24 through 26 in San Francisco. We'll be detailing the unique challenges and capabilities of building location-aware services on a new mesh networking infrastructure, one specifically designed to support stable connectivity in highly mobile networks. We will also lead a hands-on discussion of how a wide variety of technologies can be hacked to support location-aware text/chat, voice, and video services. An example case study will be undertaken to see the business case underlying a specific text, voice, and video mashup application and the resulting system will be available for open use by participants through their laptops, PDAs, and other networked devices.

We are also maintaining a blog at www.meshify.com, where we are detailing some of the lessons learned, both philosophically/theoretically as well as implementation-specific, from building location-aware applications.

Christopher Ngan is a co-founder of Aeria LLC, a startup focused on commercializing a new patent-pending, highly survivable wireless mesh algorithm.

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