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Seapilot vs qtVlm: catalog facts
Seapilot	qtVlm
Screenshots	Screenshots
Best for: Recreational boaters who want chart navigation on a phone or tablet	Best for: Cruising and racing sailors who plan routes around weather
Free + paid options Basic is free, Premium costs $39.99, and charts are bought separately except free US charts.	Free + paid options The GRIB viewer is free; mobile and tablet apps, chart packs and the GRIB service are paid.
Android, iOS	Windows, Android, iOS
AIS and NMEA sensor support in Premium Weather routing with GRIB data GPX import and export	Weather routing with departure-time comparison Reads S57, S63, raster and MBTiles charts AIS and NMEA instrument support Iridium GO certified
Charts cost extra outside the US Most navigation features require Premium	Mobile versions and chart packs are paid Wide feature set takes time to learn
Downloadable app	Downloadable app
Not open source	Not open source
License not stated	License not stated
Not stated if an account is needed	Not stated if an account is needed
Not stated if it works offline	Not stated if it works offline
Official website Full listing and sources Sources for Seapilot seapilot.com apps.apple.com/us/app/seapilot/id915818783 Catalog checked September 23, 2026	Official website Full listing and sources Sources for qtVlm meltemus.com apps.apple.com/us/app/qtvlm/id999110023 Catalog checked September 24, 2026

“Not stated” means we have not confirmed it. Features can vary by device and plan.

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