  Living lab outdoor experimentation using pervasive computing provides new
opportunities: higher realism, external validity and socio-spatio-temporal
observations in large scale. However, experimentation `in the wild' is complex
and costly. Noise, biases, privacy concerns, compliance with standards of
ethical review boards, remote moderation, control of experimental conditions
and equipment perplex the collection of high-quality data for causal inference.
This article introduces Smart Agora, a novel open-source software platform for
rigorous systematic outdoor experimentation. Without writing a single line of
code, highly complex experimental scenarios are visually designed and
automatically deployed to smart phones. Novel geolocated survey and sensor data
are collected subject of participants verifying desired experimental
conditions, for instance, their localization at certain urban spots. This new
approach drastically improves the quality and purposefulness of crowd sensing,
tailored to conditions that confirm/reject hypotheses. The features that
support this innovative functionality and the broad spectrum of its
applicability are demonstrated.
