Submarius
Global water clarity for divers
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What is Submarius?
Submarius is a mobile-first ocean conditions app for spearos, divers, fishermen, boaters, and other water users. It focuses on giving one clear answer instead of a cluttered dashboard: whether conditions are good enough to go, and why. The core idea is that you can read the ocean through a verdict system that combines visibility, fish activity, and safety signals.
Its standout feature is a real water-clarity forecast built specifically for underwater activity. The site says it uses satellite turbidity data, river-discharge plumes, wave mixing, and post-dive reports to estimate visibility, with uncertainty shown honestly rather than hidden. It also shows a bite score that combines tide, moon, solunar tables, barometric trends, and local patterns.
The app is designed around activity modes such as spearfishing, rod and reel, scuba, freediving, boating, sailing, surfing, and kayak/SUP. The interface reorders itself around the signals that matter most for the selected mode, and it explains each factor behind the GO or DON’T verdict. It also includes privacy-minded reporting, with exact dive spots kept on-device and community reports fuzzed to about 1 km.
Submarius is for people who make weather- and water-dependent decisions and want simpler guidance than a general marine app. It is especially aimed at users who care about clarity, timing, and safety features like buddy GPS sharing, SOS, shark alerts, and breath-hold monitoring. The site emphasizes honesty, transparency, and getting users to the water at the right time.
Submarius pricing
Pricing model: Freemium
Submarius has a free tier with current conditions, verdict, bite score, community spots, and all safety features available forever. The site also says there is no auth wall to start using the app. Pro unlocks 8-day forecasts, unlimited spots, premium overlays, and offline maps. The App Store listing shows $12.99/month or $99/year with a 7-day free trial, plus a limited $149 lifetime tier for the first 1,000 founders.
Submarius pros
- Real underwater-visibility forecasting
- Mode-specific GO/DON’T verdicts
- Bite score from multiple signals
- Water clarity explained with reasons
- Explicit uncertainty ranges
- Community post-dive reports improve the model
- Immersive visibility drawer visualization
- Safety features are permanently free
- Buddy GPS sharing included
- SOS feature included
- Shark tag alerts included
- Breath-hold monitoring included
- Activity modes for multiple water sports
- Privacy-preserving report location fuzzing
- Exact spots stay on device
- Offline maps in Pro
- Premium overlays in Pro
- Unlimited spots in Pro
- 8-day forecasts in Pro
- No signup required to start
Submarius cons
- Focused on water activities only
- Best value depends on local data coverage
- Some regions may lack direct clarity data
- Forecasts rely partly on proxies in some cases
- Community-driven model may improve over time only
- Offline maps require Pro
- 8-day forecasts require Pro
- Premium overlays require Pro
- Limited features for non-water users
Frequently asked questions about Submarius
What does Submarius do?
Submarius reads ocean and weather conditions and turns them into a simple GO or DON’T verdict for the water. It combines water clarity, bite score, and activity-specific conditions so spearos, divers, fishermen, and boaters can decide when conditions are worth the trip.
How does the water-clarity forecast work?
The clarity forecast is built from satellite Kd490 turbidity data, river-discharge plume detection, wave-mixing models, and post-dive visibility reports. The site says the model starts with physically grounded estimates and then improves as user reports accumulate, with uncertainty shown as a range rather than a fake-precision single number.
What is the bite score?
The bite score is a 0–10 number that answers whether now is a good time to fish. It combines tide, moon, solunar tables, barometric trend, and local patterns to cut through scattered marine data and show whether the fishing window is likely to be favorable.
Which activities does Submarius support?
The dashboard supports spearfishing, rod and reel, scuba, freediving, boating, sailing, surfing, and kayak/SUP. Users can switch modes anytime, and the app reorders the interface around the signals most relevant to the chosen activity.
Is Submarius free to use?
Yes. The site says current conditions, verdict, bite score, community spots, and every safety feature are free forever. It also says you can open the app free with no signup, and that there is no paywall for the safety tools.
What comes with Pro?
Pro unlocks 8-day forecasts, unlimited spots, premium overlays, and offline maps. The pricing shown on the App Store is $12.99 per month or $99 per year, and there is also a limited $149 lifetime option for early founders.
How does Submarius handle privacy?
Submarius says your exact dive location never leaves your device for personal logs. Community visibility reports are submitted with an H3-fuzzed coordinate of about 1 km instead of precise spots, so the model can learn from reports without exposing exact locations.
Does Submarius show uncertainty?
Yes. The site emphasizes honest uncertainty and says it avoids fake precision. For clarity, it can show ranges such as p10, p50, and p90 estimates so users see the likely spread instead of a single overconfident number.
What safety features are included?
Safety features are permanently free and include shark tag alerts, buddy GPS sharing, SOS, and breath-hold monitoring. The site frames these as features that should not be locked behind a subscription.
How does Submarius present the forecast?
Instead of a generic dashboard, Submarius gives a verdict with color-coded guidance like PRIME, GOOD, FAIR, or ROUGH. Users can tap factors to see exactly why the app says go or don’t go, and the clarity view includes a visual underwater scene that makes the visibility number easier to understand.