# SubZero vs FPA 39a

The clearest difference is in-app purchases: FPA 39a at none against SubZero's 2. FPA 39a also leads on update cadence (daily vs monthly) and device support (4 vs 2). On price, ads and iOS requirement there is nothing between them.

Both are free to download. SubZero sells 2 in-app purchases, starting at $4.99 per month. FPA 39a asks for nothing beyond the download.

SubZero ships an update monthly, FPA 39a daily. The most recent releases landed on October 18, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | SubZero | FPA 39a |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | Yes | Yes |
| Update frequency | Monthly | **Daily** |
| Size | 13 MB | 28 MB |
| Requires iOS | **17.0** | 18.0 |
| Devices | iPhone, iPad | **iPhone, iPad, Mac, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [emirhan cifci](https://appshunter.io/developer/1837498715) | [TSETSONIS DIMITRIOS KAI SIA E.E.](https://appshunter.io/developer/6787146674) |

## What reviewers say

### SubZero

[App page](https://appshunter.io/ios/app/subzero-subscription-tracker/id6760584552)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| SubZero Pro Monthly | $4.99 | per month |
| SubZero Pro Yearly | $39.99 | per year |


### FPA 39a

[App page](https://appshunter.io/ios/app/fpa-39a/id6787146672)

**Features:** Apple Watch app

**In-app purchases:** none


## Frequently asked questions

### Is SubZero free?

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

### Is FPA 39a free?

FPA 39a is free to download, with no in-app purchases.

### Do SubZero or FPA 39a have ads?

Both SubZero and FPA 39a show ads.

### Which is updated more often, SubZero or FPA 39a?

SubZero ships an update monthly, and FPA 39a daily. Most recently, SubZero was updated on October 18, 2026 and FPA 39a on October 6, 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.*