Endodontic diagnosis can be compared to a puzzle, requiring the interpretation of a series of clinical and imaging data. Mobile health, especially mobile application (apps), can assist professionals in endodontic diagnosis. This work aims to evaluate an app - Endo 10 app, designed to assist pulpal and periapical diagnosis based on the patient’s signs and symptoms and radiographic data.A total of 41 dental students and dentists with different levels of expertise (10 multi-specialty clinic professors, 17 residents in endodontics and 14 dental students) were included. The System Usability Scale (SUS) was used to evaluate usability and the Davis’ technology acceptance model was used to evaluate usefulness of Endo 10 app. The Mann-Whitney test was performed to compare SUS scores between professors and undergraduate dental students and to compare questions 6 and 7 of the utility test and verify whether participants who understood that the technology was useful also better understood the concepts of endodontic diagnosis. The agreement between professor’s diagnosis with the app and professor without the app, and between professor and residents in endodontics with the app were evaluated.The SUS score at the 50th percentile was 77.5, graded as acceptable. No significant difference was observed in the SUS scores when analyzing professors and dental students separately (p = 0.442). Usefulness test showed positive responses ranging between 72% - 100%. No statistically significant difference was observed between questions 6 and 7 of the utility test (p = 0.206), indicating that the group of participants who understood that the technology was useful in endodontic diagnosis was associated with the agreement that the application helped to better understand the concepts related. The diagnosis agreement between professor in the common diagnosis process and professor with app was 100% (31) of cases. The concordance between professor and residents in endodontics with the app was 71% (22) of cases. The differences were associated with resident’s misinterpreting the patient’s data.The Endo 10 app reached the usability and usefulness requirements. It proved accurate in diagnosing pulpal and periapical pathologies.