Smartphone-based ECG recording devices are a promising new diagnostic in veterinary medicine. However, these devices have not yet been demonstrated to work in water buffalo. A commercial, non-invasive, smartphone-based ECG (AliveCor Vet TM) monitoring device was field tested on water buffalo calves. Six neonatal water buffalo calves had an ECG simultaneously recorded with a standard medical ECG recorder and the AliveCor Vet device. A correlation of 0.75053 was observed between average heart rates obtained between AliveCor recordings when compared to those from the 6 lead ECG. 100% Rhythm agreement was met for all 12 recordings. The recordings of 4/6 calves most closely resembled lead aVR, recordings of 2/6 calves more closely resembled lead II. No significant difference was observed between standard and AliveCor quality scores (P=0.3632). We conclude that the AliveCor device allows for accurate rate diagnosis, and accurate diagnosis of a normal sinus rhythm in neonatal diary water buffalo calves in a field setting.