# SubStandard vs GRF Snowtam

The clearest difference is price: SubStandard at Free against GRF Snowtam's $1.99. SubStandard also leads on rating (5.0 vs 1.0) and iOS requirement (12.0 vs 15.6). On review sentiment, ratings volume, update cadence and ads there is nothing between them.

SubStandard is free to download; GRF Snowtam costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

SubStandard holds the better App Store score, 5.0 against 1.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively. Written reviews split almost evenly too, at 0% and 0% positive.

SubStandard ships an update every 7 months, GRF Snowtam every 4 months. Both last shipped on November 3, 2026.

## The numbers

| Metric | SubStandard | GRF Snowtam |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/substandard/id1513656520/reviews)** | [1.0 (1 ratings)](https://appshunter.io/ios/app/grf-snowtam/id1514590590/reviews) |
| Number of ratings | **2** | 1 |
| Positive reviews | 0.0% of reviews | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 4 months** |
| Monetization | **Free** | Paid |
| Size | 33 MB | 9 MB |
| Requires iOS | **12.0** | 15.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [iService Ottner Röck](https://appshunter.io/developer/1413717324) | [Pedro Isidoro](https://appshunter.io/developer/1506809339) |

## What reviewers say

### SubStandard

[App page](https://appshunter.io/ios/app/substandard/id1513656520)

This aviation utility app simplifies applying cold temperature corrections for altitudes. It allows users to save frequently used altitude sets for rapid retrieval, enhancing efficiency in flight planning.

**Highlights:** Cold temperature corrections, Altitude set storage, Quick access to saved altitudes, Easy to use interface

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

**In-app purchases:** none


### GRF Snowtam

[App page](https://appshunter.io/ios/app/grf-snowtam/id1514590590)

Decode aviation weather reports with this tool. It handles Global Reporting Format (GRF) and older Snowtam formats, converts visibility and temperature units, and calculates altitude corrections for cold weather.

**Highlights:** GRF decoder, Snowtam decoder, MOTNE decoder, Visibility converter, Temperature converter, Altitude correction calculator

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is SubStandard free?

SubStandard is free to download, with no in-app purchases.

### Is GRF Snowtam free?

GRF Snowtam costs $1.99, with no in-app purchases.

### Which has better reviews, SubStandard or GRF Snowtam?

SubStandard is rated higher. SubStandard averages 5.0 out of 5 from 2 ratings, while GRF Snowtam averages 1.0 from 1 ratings.

### Do SubStandard or GRF Snowtam have ads?

Neither SubStandard nor GRF Snowtam shows ads.

### Which is updated more often, SubStandard or GRF Snowtam?

SubStandard ships an update every 7 months, and GRF Snowtam every 4 months. Most recently, SubStandard was updated on November 3, 2026 and GRF Snowtam on November 3, 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.*