CaptainCalc: Marine Navigator

CaptainCalc is a captain-made maritime operations toolkit for ship masters, deck officers, cadets and professional seafarers. Plan voyages, work with professional tide and UKC evidence, check stability, perform celestial calculations, use bridge calculators and keep operational records in one focused Android app. ★ PROFESSIONAL TIDES, CURRENTS & UKC Use signed global FES tide predictions, NOAA high/low-water events and available current sources with visible datum, source and confidence evidence. Point UKC keeps tide, squat, safety margins and input provenance explicit. ★ VOYAGE PLANNING & OFFLINE MAPS Plan routes, manage waypoints, track progress and prepare supported regional or harbor-detail map packs before coverage drops. ★ GMDSS DECISION SUPPORT Prepare DSC distress, urgency and safety worksheets, readiness checks, authorized radio-log records, and MSI/NAVTEX review with source provenance. CaptainCalc does not transmit, control radio equipment, acknowledge or relay alerts, or replace certified GMDSS equipment and approved procedures. ★ DRAFT SURVEY, STABILITY, CARGO & TANKS Support six-draft surveys, hydrostatic interpolation, loading conditions, stability checks, cargo planning and tank sounding workflows. Results are decision support and must be verified against approved vessel data. ★ CELESTIAL NAVIGATION & BRIDGE CALCULATORS Work sun, moon and star observations, sight reductions and fixes. Use practical calculators for ETA, CPA/TCPA, set and drift, fuel, squat and routine bridge checks. ★ RECORDS, EXPORTS & REFERENCES Keep voyage and calculation records together, export supported PDF/CSV/GPX/KML outputs, and access COLREG, IALA and maritime reference material. ★ CAPTAIN'S LOUNGE Join a text-only maritime discussion space for ports, routes, weather, cargo, stability and app tips. Community rules, reporting, blocking and moderation keep the Lounge focused on professional use. FREE & PREMIUM ACCESS Freemium is ad-supported and keeps essential tools available while online. Premium removes ads, increases usage limits and unlocks the full professional suite, including offline access and optional encrypted cloud backup/restore. Cloud backup supports up to 10 restore points, keeps eligible backups available for up to 30 days after Premium ends and does not provide live sync. Google Play manages purchase, renewal and cancellation. IMPORTANT CaptainCalc supports maritime work and training. It does not replace approved stability booklets, loading computers, ECDIS, official nautical publications, company procedures, statutory documentation or the master's professional judgment. Users remain responsible for all operational decisions.