When is the fasting person’s supplication answered: Is it before breaking the fast, during it, or after it? And have any Prophetic supplications been reported specifically for this time?

The supplication (Du'a) should be made before breaking the fast at sunset, due to the convergence of humility, submissiveness, and fasting, which are all reasons for the supplication to be answered. As for after breaking the fast, the following supplication has been narrated: "Thirst has gone, the veins are moistened, and the reward is confirmed, if Allah wills." Some Companions also used to say: "O Allah, for You I have fasted, and with Your provision I have broken my fast."