Iftar, refers to the evening meal for breaking the daily fast during the Islamic month of Ramadan. Or a meal served at the end of the fasting day during Ramadan, to break the day's fast. Literally, "breakfast." Iftar during Ramadan is often done as a community, with Muslims gathering to break their fast together.
The time for Iftar is 12 to 15 minutes after Sunset. It is better to offer 'Magrib Namaz/salat' and then break one's fast, preferably with water, milk or dates.
The following Dua may be recited at the time of breaking one's fast:
اللَّهُمَّ لَكَ صُمْتُ وَ عَلَى رِزْقِكَ أَفْطَرْتُ وَ عَلَيْكَ تَوَكَّلْتُ
ALLAAHUMMA LAKA S'UMTU WA A'LAA RIZQIKA AFT'ARTU WA A'LAYKA TAWAWKKALTU
O my Allah, for Thee, I fast, and with the food Thou gives me I break the fast, and I rely on Thee
بِسْمِ اللَّهِ اللَّهُمَّ لَكَ صُمْنَا وَ عَلَى رِزْقِكَ أَفْطَرْنَا فَتَقَبَّلْ مِنَّا إِنَّكَ أَنْتَ السَّمِيعُ الْعَلِيمُ
BISMILLAAH ALLAAHUMMA LAKA S'UMNAA WA A'LAA RIZQIKA AFT'ARNAA FA-TAQABBAL MINNAA INNAKA ANTAS SAMEE-U'L A'LEEM
In the name of Allah, O Allah, we fast, and with the food Thou gives us we break the fast, an obligation we fulfill, and Thou art Hearer, Knower
While taking the first mouthful recite:
بِسْمِ اللَّهِ الرَّحْمَنِ الرَّحِيمِ يَا وَاسِعَ الْمَغْفِرَةِ اغْفِرْ لِى
BISMILLAAHIR RAH'MAANIR RAH'EEM YAA WAASI-A'L MAGHFIRATI IGHFIR LEE
In the name of Allah, the Beneficent, the Merciful, O He whose indulgence is boundless, forgive me.
source : www.tebyan.net