Field Methods, Ahead of Print.
Household expenditure data is at the core of efforts to measure living standards, inequality and financial protection against illness. Currently it is mainly derived from recall-based surveys that are time consuming and prone to measurement errors. Diaries are often used as an alternative approach, however this results in fatigue and low compliance. Smartphone- based diaries could overcome many of these challenges, but it is yet unknown how this approach could be used and its relationship with data from the household surveys. This study evaluated a smartphone-based diary application for collecting daily household expenditures and compared data with that of household surveys. Results show that smartphone-based diary applications could be used to optimize or complement the information from conventional survey-based indicators.