The First World War (1914-1918) or as it is also called the Great War in the Serbian army gave birth to many known and unknown heroes. Among the well-known heroes of the mentioned war is Dušan Dodić, a cavalry officer who was on duty in the Cavalry Division. Commanding the operational division of the Cavalry Division at the time of the breakthrough of the Thessaloniki front, he contributed to the breakthrough of the front and stood out during the pursuit of the defeated enemy, performing bold incursions that brought surprises. He liberated many places in Macedonia and Serbia, forced the Danube near Smederevo and took a number of places in Banat. For his successful work, he was praised by the competent command and decorated with numerous domestic and foreign decorations. He left precious records about those glorious days in the form of a war diary. The diary that is part of the legacy of Dušan Dodić, which is kept in the collection of the History Department of the Homeland Museum in Jagodina, was a good starting point to create an application about Dušan Dodić, one of the heroes of the Great War.