Submarius
When conditions are right,
you'll know.
Submarius is a mobile-first app for spearos, divers, fishermen, and boaters. Real water-clarity forecasts, honest bite scores, and a verdict — not another dashboard — for every activity on the water.
Anonymous-first. Safety features permanently free. No auth wall.
Water clarity forecast
The only app that predicts how far you'll see underwater. Satellite Kd490 turbidity, river-discharge plumes, wave mixing, and post-dive reports feed a physically-grounded visibility model. Honest uncertainty, not wishful thinking.
How clarity works →Bite score
A 0–10 number answering "is now a good time to fish?" — combining tide, moon, solunar tables, barometric trend, and local patterns. Cuts through the noise so you get to the water at the right hour.
What is a bite score? →Safety, always free
Shark tag alerts (OCEARCH), buddy GPS sharing, SOS, and breath-hold monitoring are permanently free — no Pro gate, no paywall. Some features shouldn't cost money.
A verdict, not a dashboard.
Every other fishing app throws numbers at you — wind, swell, tide, moon, pressure, twelve species cards — and leaves the decision to you. Submarius reads those signals and gives you one answer: GO or DON'T. Color-coded. Explainable. Tap any factor to see exactly why.
Designed for every activity
Pick your mode — the dashboard reorders itself around the signals that matter for that activity. Multi-select supported. Switch anytime.
Free to start.
Current conditions, verdict, bite score, community spots, and every safety feature are free forever. Pro unlocks 8-day forecasts, unlimited spots, premium overlays, and offline maps.