In the arsenic-contaminated Ganges-Brahmaputra-Meghna Delta in Bangladesh and India, small-scale piped water supply (SPWS) seems a promising way to provide safe drinking water to the households. End-user participation is important to root water interventions in the local context, and the use of smartphone applications can support local participation. In this region, smartphone use and internet access are growing rapidly and smartphone applications could enable real-time water quality monitoring, water bill payment, and a dialogue between end-user and water supplier. This research investigates the opportunity for and interest in the use of mobile crowd participation for SPWS monitoring.