ShabbatSync

ShabbatSync is a mobile + web app that prevents the most common cross-community friction: mismatched Jewish dates, candle-lighting times, Yom Tov start/end, and Israel-vs-diaspora holiday differences. Users create “circles” (family, school, workplace, travel group) with each member’s location and minhag preferences (Israel, diaspora; major nusach options). The app generates a shared, conflict-free schedule for events, calls, deadlines, and travel plans, with automatic warnings like “Your team in Tel Aviv is on Yom Tov; you’re not” or “Candle lighting in London is 18 minutes earlier than your usual.” It also includes travel mode that recalculates zmanim and halachic date boundaries as you move. This is a traditional app with a small AI layer for natural-language event parsing (e.g., “schedule dinner after Shabbat in Jerusalem”).