TapBack: towards richer mobile interfaces in impoverished contexts

Much of the mobile work by HCI researchers explores a future world populated by high-end devices and relatively affluent users. This paper turns to consider the hundreds of millions of people for whom such sophistication will not be realised for many years to come. In developing world contexts, people will continue to rely on voice-primary interactions due to both literacy and economic reasons. Here, we motivate research into how to accommodate advanced mobile interface techniques while overcoming the handset, data-connection and user limitations. As a first step we introduce TapBack: back-of-device taps to control a dialled-up, telephone-network-based voice service. We show how these audio gestures might be recognised over a standard telephone connection, via users' existing low-end devices. Further, in a longitudinal deployment, the techniques were made available on a live voice service used by rural Indian farmers. Data from the study illustrates the desire by users to adopt the approach and its potential extensions.