GeoStorm vs Marlin
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
GeoStorm
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GeoStorm is the all-in-one weather and visualization tool. Whether you’re a professional mariner, an avid hiker, or an aurora chaser, GeoStorm integrates high-quality data from with real-time tracking to keep you informed. Explore Our Core Modules: Sky & Space: Never miss a moment with precise Sun and Moon positioning. Use our Satellite Imagery (Beta) to see the world from above and stay updated with live Northern Lights (Aurora) observations reported over the last 24 hours. Sea & Navigation: Set sail with confidence using official Nautical Charts. Monitor maritime activity with live Ship tracking (Beta) and stay ahead of the game with the latest Fishing & Catch reports. Land & Wilderness: Master the terrain with detailed Topographic Maps. Discover new heights with our Mountain Peak (Beta) database and explore local biodiversity through integrated Species Observations.
Marlin
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The living pulse of your coastline. Marlin turns every marina into a live window on the sea. A network of solar-powered sensor stations measures the real conditions in the harbor and delivers them live, so you always know what the water is doing right now. Six live values, around the clock: water temperature, wave height, wind, water level, air pressure and air temperature. BUILT FOR THE PEOPLE ON THE COAST Sailors: check wind and waves at your marina before you head out. Harbor masters and operators: keep the whole port in view, right from the office. Research and curious minds: explore reliable, continuous coastal data. WHY MARLIN Hyperlocal, not regional. We measure at the exact marina, where general forecasts fall short. Measured, not modeled. Real sensor readings, not distant predictions. Live and continuous. Always current, and always building a long-term record. FEATURES Live sensor map: see real-time conditions across every marina at a glance. Detailed dashboards: dive into the full picture for each station. History and trends: explore past measurements and spot patterns over time. Smart notifications: get push or email alerts the moment a reading crosses your threshold. Open data: transparent access that supports research and innovation across the maritime sector. Born from ocean research in Kiel, Marlin makes the coast readable for everyone who depends on the water. Your coast, live. Download Marlin and see what your marina is doing right now.
Screenshots
Verdict
GeoStorm and Marlin are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Both ship on a similar rhythm, roughly every 5 weeks. The most recent releases landed on October 8, 2026 and October 5, 2026 respectively.
| Parameter | GeoStorm | Marlin |
|---|---|---|
| Price | Free | Free |
| Update frequency | Every 5 weeks | Every 5 weeks |
| Ads | No | No |
| In-app purchases | No | No |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.0 | 15.0 |
| Further details — not scored | ||
| Size | 74 MB | 37 MB |
| Age rating | 4+ | 4+ |
| Developer | Jon-Remi Bredesen | Tarek Almohamad |
In-app purchases
GeoStorm
No in-app purchases
Marlin
No in-app purchases









