Comparison

Flood Map USA vs CoastWarn

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Flood Map USA

This app helps you identify flood-prone areas near a specific U.S. street address. It can generate printable maps or interactive overlays based on available FEMA flood study data. Useful for risk assessment before or after severe weather events.

Highlights
  • Flood zone identification by address
  • FEMA flood study data integration
  • Printable PDF flood maps
  • Interactive map (beta)
  • Risk assessment tool
  • Supports U.S. addresses
Features
Read full description

Flood Risk Map Maker displays a map that shows the flood-prone areas near a given street address in the United States. Identify flood zones to watch out for after a rainstorm, tropical storm, or hurricane. To use: - Type your street address - Tap "Get Flood Risk Map" Depending on the availability of the flood study data in your area, this app will generate one of the following results: - Areas with modern digital FEMA flood study data: A printable PDF showing about 400 acres or about 0.6 sq. mi. - Areas with old FEMA flood study data: A scanned image of an older printed map - Remote areas where a FEMA flood study has not been conducted: No map available - Interactive map (beta): Pan and zoom a live map with color-coded flood zone overlays Ideal for: - Homeowners and home buyers - Real estate agents - Farmers - Insurance professionals - Businesspeople - Anyone doing a risk assessment or asking "Am I in a flood zone?" Ad-supported. If you like the app, please consider upgrading to remove the ads and support future development.

About

CoastWarn

Receive timely alerts for coastal flooding based on your custom water-level thresholds. Monitor NOAA data, get tide charts, and stay informed about potential flood events affecting your property or boat.

Highlights
  • Customizable flood alert thresholds
  • NOAA water-level monitoring
  • Tide charts and predictions
  • Flood expected notifications
  • Alert history
  • Station map search
Features
Read full description

CoastWarn monitors official NOAA water-level data and alerts you when observed levels reach the threshold you set. If you live, work, or keep a boat on the coast, you know the drill: nuisance flooding that soaks your car, a dock line that needs more slack, a driveway that disappears at high tide. CoastWarn helps you keep track of the water levels that matter to you. HOW IT WORKS - Find a supported NOAA station using your ZIP code or the station map. - Set the water-level threshold that matters to your property or boat. - Receive flood alerts and all-clear notifications, with current readings and trends. - See “Flood Expected” notices when supported regional forecasts predict your threshold will be reached. BUILT FOR COASTAL REALITY - Official NOAA CO-OPS water-level observations and tide predictions. - Adjustable alert thresholds at eligible stations. - Time-sensitive notifications for minor-or-higher flood alerts, subject to your iPhone’s notification settings. - Tide charts and regional model projections where available. - Alert history, monitoring status, and notices when monitoring is interrupted. WHO IT’S FOR Waterfront homeowners · boaters and marina tenants · coastal businesses · anyone who lives with a rising tide TRY IT FREE CoastWarn is free for 7 days. Continue with CoastWarn Pro Lifetime: a single $19.99 purchase that unlocks the app’s features with no subscription or renewal. No user account required. Restore Purchases is available in Settings. Data, forecasts, and alert monitoring vary by station. Alert delivery depends on current data, connectivity, notification permissions, and iOS scheduling. CoastWarn supplements official warnings; always follow National Weather Service guidance and local emergency instructions.

Screenshots

Flood Map USA4 screens
CoastWarn4 screens

Verdict

The call

The clearest difference is ads: CoastWarn at none against Flood Map USA's shown. CoastWarn also leads on update cadence (every 6 days vs monthly). Flood Map USA's advantage is monetization model (ad-supported vs free with in-app purchases) and ratings volume (3 vs 1). On price, rating, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Flood Map USA sells 1 one-off in-app purchase and CoastWarn sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for Flood Map USA against 5.0 for CoastWarn. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

UpkeepUpdate frequency

Flood Map USA ships an update monthly, CoastWarn every 6 days. The most recent releases landed on October 6, 2026 and October 3, 2026 respectively.

Scorecard4 real differences · 5 level
Flood Map USA versus CoastWarn: the parameters behind the verdict, then further details
ParameterFlood Map USACoastWarn
PriceFreeFree
Rating5.0 (3 ratings)5.0 (1 ratings)
Number of ratings3 — better1
Update frequencyMonthlyEvery 6 days — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationAd-supported — betterFree with in-app purchases
DevicesiPhone, iPad — betteriPhone
Requires iOS16.0 — better17.0
Further details — not scored
Size4 MB3 MB
Age rating4+4+
DeveloperQvyshift LLCRyan Dean

Customer experience

Flood Map USA

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

CoastWarn

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

1 purchases

Flood Map USA

One-time1
  • Upgrade$6.99
1 purchases

CoastWarn

One-time1
  • CoastWarn Lifetime Unlock$19.99

Questions

Is Flood Map USA free?
Flood Map USA is free to download, with in-app purchases available.
Is CoastWarn free?
CoastWarn is free to download, with in-app purchases available.
Which has better reviews, Flood Map USA or CoastWarn?
Flood Map USA and CoastWarn are both rated 5.0 out of 5 on the App Store, from 3 and 1 ratings respectively.
Do Flood Map USA or CoastWarn have ads?
Flood Map USA shows ads; CoastWarn does not.
Which is updated more often, Flood Map USA or CoastWarn?
Flood Map USA ships an update monthly, and CoastWarn every 6 days. Most recently, Flood Map USA was updated on October 6, 2026 and CoastWarn on October 3, 2026.

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