Improving Smartphone Sustainability by Reusing Discarded Devices (Complete)
Electronic waste is a growing problem as the rapid pace of technological improvements drives consumer appetites for the latest and greatest devices. Smartphones are already part of this problem, and given the rate of progress in the smartphone technologies, it seems reasonable to expect that consumers will dispose of these devices at rapid rates, spurred on by new features and discounts offered by carriers. Fortunately, the capabilities of smartphones make discarded devices ideal building blocks for many second uses. We have explored reusing the discarded smartphones generated by PhoneLab in multiple ways: as environmental sensors, to create a city-scale sensor network, and as part of personal storage clouds.
Smartphone technologies are advancing rapidly, bringing new power into users pockets and changing the way that we live and work. The rapid rate at which consumers purchase new smartphones can be seen as primarily a response to the rate at which this technology is improving. Short device lifetimes, while unfortunate from a sustainability perspective, help support companies that build and sell smartphone hardware and software. Unfortunately smartphones, like most other electronics, are difficult to dispose of properly. Many end up in landfills or shipped to poor countries where they are dangerously dismantled in an effort to collect precious materials.
Given the potential of the smartphone to bring about transformative technological change, it becomes difficult to reduce demand by arguing that consumers should hang on to outdated devices in the name of sustainability. Instead, we propose to focus on the supply of fully- or partially-functional outdated devices that society currently struggles to put to use, and explore how this growing volume of techno-trash can be efficiently reused.
There are three reasons why the time is right for this effort. First, unlike previous generations of "feature phones", the current smartphone market is coalescing around a small set of common platforms such as Android. This platform homogeneity reduces the burden of supporting large numbers of discarded devices. Second, current smartphones have an attractive feature set for many non-phone applications: size and power requirements facilitating easy deployment, microphones and cameras allowing them to double as sensors, touch screens for interfacing with users.
Finally, smartphones are well-integrated into the existing communication infrastructure. They can transmit data via text messages, over Wifi networks, and via high-speed mobile communication technologies like 3G. If Wifi is available, no service plans are required to allow recycled smartphones to become part of the "Internet of Things". And with carriers increasingly interested in "machine-to-machine" applications, we expect to see increasing service flexibility allowing discarded devices to be cheaply connected to pervasive mobile cellular and data networks.
To provide an idea of the potential of discarded devices, the U.S. Environmental Protection Agency (EPA) estimated that 141~million mobile devices became ready for end-of-life management in 2009, of which only 11.7 million (8%) were collected for recycling. The 129~million phones discarded in 2009 would be enough to place an average of 200 phones on all 600,000~bridges in the United States, or every 2 feet on every stretch of highway in the 46,876~mile interstate highway system.
Inspired by the several hundred discarded devices blue receives through the PhoneLab project, we set out to explore several potential second uses—particularly to facilitate other ongoing research efforts. Our HotMobile'14 paper takes a cheeky turn on the project by suggesting that discarded smartphones would be an ideal replacement for many of the uses originally imagined for sensor network "motes". Since then we have continued to leverage our supply of discarded smartphones for multiple purposes:
University at Buffalo Linguistics Professor Jeff Good has taken several of our discarded devices to Cameroon to help preserve a dying language.
We are turning discarded smartphones into navigation devices as a way to "sneak into cars" as part of the Navjack project.
We are investigating multiple ways to allow users to continue to use discarded smartphones as part of a growing "personal cloud" of devices—for example, to provide additional storage available to other nearby devices.