# FDR Calculator vs Storm Distance Tracker

The clearest difference is ads: FDR Calculator at none against Storm Distance Tracker's shown. Storm Distance Tracker's advantage is review sentiment (33% vs 0%). On price, update cadence, in-app purchases and monetization model there is nothing between them.

Both are free to download. FDR Calculator sells 2 in-app purchases, starting at $1.99 per month and Storm Distance Tracker sells 4 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

FDR Calculator ships an update every 4 months, Storm Distance Tracker every 7 months. The most recent releases landed on October 23, 2026 and October 21, 2026 respectively.

## The numbers

| Metric | FDR Calculator | Storm Distance Tracker |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.7 (101 ratings)](https://appshunter.io/ios/app/storm-distance-tracker/id1123064491/reviews)** |
| Number of ratings | — | **101** |
| Positive reviews | 0.0% of reviews | **33.3% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Every 4 months** | Every 7 months |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 35 MB | 31 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Alan Richert](https://appshunter.io/developer/527055673) | [DOUBLE U s.r.o.](https://appshunter.io/developer/331787042) |

## What reviewers say

### FDR Calculator

[App page](https://appshunter.io/ios/app/fdr-calculator/id527055670)

Instantly calculate fire danger ratings with professional-grade algorithms. Offers real-time weather data integration, visual danger level displays, and detailed action recommendations for informed fire prevention and management.

**Highlights:** Instant Fire Danger Index calculations, Real-time weather data integration, Visual color-coded danger levels, Detailed action recommendations, Manual calculator for offline use, Automatic location detection

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weather Pro (Monthly) | $1.99 | per month |
| Enable Local Weather | Free | one-time |


### Storm Distance Tracker

[App page](https://appshunter.io/ios/app/storm-distance-tracker/id1123064491)

Measure the distance to a storm by timing the interval between seeing lightning and hearing thunder. This tool uses the difference in the speed of light and sound to provide an estimated distance.

**Highlights:** Calculate storm distance, Uses lightning and thunder timing, Calculates based on speed of light and sound, Simple tap interface

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove ads | $1.99 | one-time |
| Remove Ads | $2.99 | one-time |
| Remove Ads | $4.99 | one-time |
| Remove Ads | $9.99 | one-time |


## Frequently asked questions

### Is FDR Calculator free?

FDR Calculator is free to download, with in-app purchases available.

### Is Storm Distance Tracker free?

Storm Distance Tracker is free to download, with in-app purchases available.

### Do FDR Calculator or Storm Distance Tracker have ads?

Storm Distance Tracker shows ads; FDR Calculator does not.

### Which is updated more often, FDR Calculator or Storm Distance Tracker?

FDR Calculator ships an update every 4 months, and Storm Distance Tracker every 7 months. Most recently, FDR Calculator was updated on October 23, 2026 and Storm Distance Tracker on October 21, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*