spearo vs Marla, SpearFactor and DiveSight
spearo, Marla Blue, SpearFactor and DiveSight solve related but different jobs. Marla is strongest for visibility science and algae signals in the four regions it covers. SpearFactor is the free California specialist, with buoy data and local species forecasts. DiveSight is broader for dive tourism and global marine-life discovery. spearo is the spearfishing-specific option: 26 countries, 1152 cities, legal packs, no-take zones, webcams, buoys and 9 languages.
An honest comparison starts with the use case. Marla Blue is built around underwater visibility, satellite imagery, algae levels, community reports and native apps. SpearFactor turns NOAA, CDIP and National Weather Service feeds into a California-local read, including species-specific forecasts and 7-day windows. DiveSight uses ML models to forecast visibility and marine-life abundance across 28,000+ dive sites, with a clear discovery focus for divers. spearo is narrower by activity and wider by spearfishing geography: it covers 26 countries and 1152 coastal cities, then adds GO / BORDERLINE / NO-GO verdicts, per-country legal packs, no-take polygons, verified webcams, buoys and 9 languages. The right choice depends on where you dive and what question you need answered before entering the water.
Compare
| Feature | Spearo | Marla | Spearfactor | Divesight |
|---|---|---|---|---|
| Primary job | Spearfishing forecast with GO / BORDERLINE / NO-GO verdicts, local rules and no-take zones. | AI underwater visibility model with wind, swell, tide, weather, algae levels and community diver reports. | Free California conditions dashboard with visibility, species forecasts and a spearfishing opportunity read. | ML marine-life abundance and visibility forecasts for dive tourism and species discovery. |
| Coverage | 26 countries and 1152 coastal cities. | 4 regions: UK, Ireland, Australia and California. | California only, from San Diego to Humboldt. | Global, with 28,000+ dive sites across 1,400+ regions. |
| Spot database | 398 official-GIS spots and 166 hard no-take polygons, plus published coastal cities. | 800+ curated named dive spots. | 30+ spots in the conditions tool; 325 spots in the trip optimizer. | 28,000+ dive sites, 1,400+ regions and custom coordinate sites. |
| Forecast style | Safety-oriented GO / BORDERLINE / NO-GO verdict for spearfishing. | Per-spot visibility forecast, algae chart, confidence score and starred-spot notifications. | Visibility estimate in feet, species activity and 7-day morning, midday and evening windows. | 0-100 Marine Life Index, visibility, depth temperatures, currents, waves, tides and monthly climatology. |
| Data sources | Open-Meteo Marine + Forecast, ECMWF/GFS/ICON ensemble, CMEMS transparency, IPMA, buoys and webcams. | Satellite imagery, weather, sea conditions and community reports; premium includes recent satellite imagery down to 300x300 m. | NOAA, CDIP, National Weather Service, wind, swell, SST, chlorophyll, rainfall, buoy data and diver-report validation. | NASA, NOAA, ESA, Copernicus Marine, HYCOM and two proprietary ML models. |
| Legal and no-take layer | Per-country legal packs, localized legal glossary and fail-close no-take polygons. | No observable spearfishing legal or no-take-zone layer. | No observable spearfishing legal or no-take-zone layer. | No spearfishing legal, take-rule or no-take-zone layer. |
| Webcams and buoys | 136 verified webcams with kill-switches and 74 verified NDBC buoys. | No observable webcams or named-buoy layer. | Uses buoy data, but lists no webcams. | No observable webcams or named-buoy layer. |
| Languages | 9 verified languages. | English only, observable. | English only, observable. | Not specified. |
| Price and model | Free, with no account or sign-up required. | Freemium; free for today at 800 spots, premium monthly/annual for tomorrow, history, any pin, hourly weather, satellite and algae. | Free; installable as a PWA and works offline once installed. | Freemium; free with 15,000+ sites, 3,000+ species and today conditions; Pro weekly, monthly or annual. |
| Platforms | Web site at spearo.app, no sign-up required. | Native iOS and Android apps; marketing website only, no full web app. | Web and installable mobile-friendly PWA. | iOS now; Android and web app in development. |
Verdict
FAQ
Is spearo free?
Yes. spearo is free and needs no account or sign-up.
Is Marla better than spearo?
For visibility, algae science, native apps and the four supported regions, Marla has clear advantages.
Is SpearFactor better for California?
Yes. It is a deep California-local tool with NOAA, CDIP, buoys, species forecasts and 7-day windows.
Where does spearo win?
In the combination of 26-country coverage, 1152 cities, per-country legal packs, no-take polygons, webcams, buoys and 9 languages.