This archive contains files containing data from Project Environmental behaviour data collected through smartphones in a field-experimental setup (pilot study). The following files have been archived: 1. PilotData_Smartphones.csv: CSV file containing the dataset generated through daily data collection via smartphones from 20 study participants for two weeks in June 2017 in the UK in a field-experimental setup. The generated data is based on the SmartphoneApplicationQuestionnaire.pdf. The dataset contains 162 variables and 286 observations. The anonymous individual identifier is username, which is the same across the three archived datasets. The field-experimental intervention was implemented in the second week of data collection and consists of two interventions (1) group intervention, i.e. social monitoring and (2) individual intervention, i.e. behavioural targeting (see Variable Catalogue Codebook Smartphone Data.pdf). 2. Variable Catalogue Codebook Smartphone Data.pdf: This file contains descriptions, including explanations of how some variables have been calculated from others, for the variables in the file PilotData_Smartphones.csv 3. SmartphoneApplicationQuestionnaire.pdf: The file shows the questionnaire implemented in the smartphone application EpiCollect 5 through which data was collected for this project. This questionnaire generated the dataset contained in file PilotData_Smartphones.csv. 4. InitialSurvey.csv: CSV file contains the dataset generated through an online survey prior to the daily two-weeks data collection via smartphones. The generated data is based on the InitialSurveyQuestionnaire.pdf. The dataset contains 7 variables and 20 observations for the 20 study participants. The anonymous individual identifier is username, which is the same across the three archived datasets. 5. Variable Catalogue Codebook Initial Survey.pdf: This file contains descriptions for the variables in the file InitialSurvey.csv 6. InitialSurveyQuestionnaire.pdf: The file shows the questionnaire implemented online through which survey data was collected prior to the smartphone-based data collection. This questionnaire generated the dataset contained in file InitialSurvey.csv 7. FinalSurvey.csv: CSV file contains the dataset generated through an online survey after the daily two-weeks data collection via smartphones. The generated data is based on the FinalSurveyQuestionnaire.pdf. The dataset contains 8 variables (incl. open text answers) and 20 observations for the 20 study participants. The anonymous individual identifier is username, which is the same across the three archived datasets. 8. Variable Catalogue Codebook Final Survey.pdf: This file contains descriptions for the variables in the file FinalSurvey.csv 9. FinalSurveyQuestionnaire.pdf: The file shows the questionnaire implemented online through which survey data was collected after the smartphone-based data collection. This questionnaire generated the dataset contained in file FinalSurvey.csv