# Winter OPS vs Holdover Calculator

The clearest difference is review sentiment: Holdover Calculator at 83% against Winter OPS's 0%. Winter OPS's advantage is monetization model (free with in-app purchases vs subscription) and iOS requirement (15.0 vs 26.0). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Winter OPS sells 7 in-app purchases, starting at $7.49 per year and Holdover Calculator sells 1 in-app purchase, starting at $9.99 per year. Whichever you choose, the download price is not the number that matters.

Both ship on a similar rhythm, roughly every 8 months. The most recent releases landed on September 12, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | Winter OPS | Holdover Calculator |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 0.0% of reviews | **83.3% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 8 months | Every 8 months |
| Monetization | **Free with in-app purchases** | Subscription |
| Size | 65 MB | 23 MB |
| Requires iOS | **15.0** | 26.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [Avimont GmbH](https://appshunter.io/developer/488879220) | [Kilo Lima Management, LLC](https://appshunter.io/developer/767164799) |

## What reviewers say

### Winter OPS

[App page](https://appshunter.io/ios/app/winter-ops/id488881673)

This application assists with de-icing and anti-icing procedures by providing holdover time calculations based on official guidelines. It also decodes SNOWTAMs and offers customizable alerts for approaching expiry times, aiding aviation operations in winter conditions.

**Highlights:** Holdover Time (HOT) calculations, SNOWTAM decoding, Customizable expiry time alerts, Qualified fluid information, Weather definitions, Dark mode support

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 year generic Fluids (FAA) | $7.49 | per year |
| 1 year generic Fluids (EASA) | $7.49 | per year |
| 1 year generic Fluids (TC) | $7.49 | per year |
| 1 year all Fluids (FAA) | $12.49 | per year |
| 1 year all Fluids (EASA) | $12.49 | per year |
| 1 year all Fluids (TC) | $12.49 | per year |
| Decoder Enabling | $1.49 | one-time |


### Holdover Calculator

[App page](https://appshunter.io/ios/app/holdover-calculator/id768019181)

This tool simplifies the calculation of aircraft de-icing fluid holdover times. It offers manual input or automatic weather data retrieval for quick and accurate results. The app provides alerts for expired times and includes a pre-takeoff check timer.

**Highlights:** Accurate holdover time verification, User-friendly input display, Automatic METAR weather retrieval, Location-based METAR search, Active holdover time countdown, Audible and visible expiration alerts, Pre-takeoff contamination check timer

**Features:** Apple Watch app

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 Year Subscription | $9.99 | per year |


## Frequently asked questions

### Is Winter OPS free?

Winter OPS is free to download, with in-app purchases available.

### Is Holdover Calculator free?

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

### Do Winter OPS or Holdover Calculator have ads?

Neither Winter OPS nor Holdover Calculator shows ads.

### Which is updated more often, Winter OPS or Holdover Calculator?

Winter OPS ships an update every 8 months, and Holdover Calculator every 8 months. Most recently, Winter OPS was updated on September 12, 2026 and Holdover Calculator on September 22, 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.*