On an everyday basis, employees may be subjected to low intensity negative behaviours from those they work with. Uncivil behaviours may cumulatively add up over time to have detrimental effects on employees' wellbeing and commitment to stay with their organisation. Since most of the research has been cross-sectional, capturing a snapshot in time, knowledge regarding the day-to-day effects of experiencing workplace incivility is limited The broad aim of the present research was to develop a new data collection tool in the form of a digital diary Smartphone app, to explore these day-to-day effects, measuring face-to-face and online workplace incivility. Three studies were conducted to develop and test the app. The first pilot study sought to test the proposed measures for use in the app. In particular, the commonly used Workplace Incivility Scale (WIS) was adapted to apply to online as well as face-to-face interactions. Statistical analysis of this pilot confirmed that both the face-to-face and online versions of the WIS were reliable and valid, and determined that experiencing workplace incivility via both modes was significantly associated with emotional exhaustion, and intentions to quit. On the basis of the first pilot, the app was developed and its feasibility tested in a second pilot focusing on the usability of the new app, which resulted in minor design changes being implemented prior to the final launch. The main research study sought to validate the new app and test a series of hypotheses about the day-to-day effects of workplace incivility. Participants completed an initial web-based survey and were then instructed to complete the questions on the app for one month. Multilevel analyses revealed that employees experienced higher levels of emotional exhaustion, and intention to quit on days when they were exposed to face-to-face or online incivility. The amount of incivility that participants experience on a day-to-day basis (Level 1) predicts emotional exhaustion, and intention to quit on a daily basis, and the average amount of incivility (Level 2) that participants experience also predicts their emotional exhaustion, and intention to quit when not considering other factors. Anger and fear were found to mediate the relationship between both forms of incivility and intention to quit. For the rumination-mediated models, the relationship between both forms of workplace incivility and emotional exhaustion is significantly mediated by rumination. Theoretically, this research contributes by providing insight into workplace incivility and its effects on a daily basis. Methodologically, this research advances the field by providing a new reliable and valid repeated measures data collection tool that other researchers may share to overcome and build upon the limitations inherent in cross-sectional studies.