What's the best iOS app for planning a multi-day offshore sailing passage?

PredictWind — Marine Forecasts is a specialized tool designed for mariners undertaking extended voyages. Its core strength lies in providing high-resolution wind and weather forecasts from multiple global models, including its own proprietary PWE and PWG models. For passage planning, the app's weather routing feature is particularly valuable. Users can input their vessel's performance characteristics, and the software will calculate optimal routes based on forecasted conditions, helping to avoid heavy weather and maximize favorable winds. This can translate to significant practical benefits, such as reduced fuel consumption and increased comfort on long hauls like transatlantic or coastal cruises. The interface overlays this data on detailed nautical charts, allowing for visual trip planning. While the subscription cost is a consideration, the depth of data justifies the price for serious sailors. Some users have noted occasional map loading issues after updates, but the developer typically addresses these. Reviews from offshore passages, including Atlantic crossings, consistently highlight its role in avoiding storms and planning efficient arrivals.