Uptake of HIV testing remains low among men in South Africa. As part of a trial, we assessed the acceptability of a theoretically derived and adapted tablet-based-application (EPIC-HIV1) in rural South Africa. We conducted 20 in-depth interviews with men aged >/=18 years and offered a tablet-based survey to all men aged >/=15 years who received EPIC-HIV1 (Sep-Dec 2018). We conducted a descriptive analysis of the survey and used Self-Determination Theory (SDT) to guide our thematic analysis. A total of 232/307 (75%) completed the survey, 55% of whom were aged 15-24 years. 96%[ CI: 92.8-98.2%; n = 223] found EPIC-HIV1 acceptable and 77% [95% CI: 71.8-82.6%; n = 179] found it user-friendly. 222 [96%] reported that EPIC-HIV1 motivated them to test; 83% (192/232) tested for HIV, of which 33% (64/192) were first time testers. Those who did not consent (n = 40) were more likely to have had an HIV-positive test result. Participants reported that the app boosted their confidence to test. However, they were unsure that the app would help them overcome barriers to test in local clinics. Given reach and usability, an adapted SDT male-tailored app was found to be acceptable and could encourage positive health-seeking behavioural change among men.