# CO2 Filter Calc vs BabalaVPN

The clearest difference is in-app purchases: CO2 Filter Calc at none against BabalaVPN's 4. CO2 Filter Calc also leads on iOS requirement (14.0 vs 16.0). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. BabalaVPN sells 4 in-app purchases, starting at $3.99 per 7 days. CO2 Filter Calc asks for nothing beyond the download.

CO2 Filter Calc ships an update weekly, BabalaVPN every 9 days. Both last shipped on October 27, 2026.

## The numbers

| Metric | CO2 Filter Calc | BabalaVPN |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Weekly** | Every 9 days |
| Size | 1 MB | 32 MB |
| Requires iOS | **14.0** | 16.0 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [TOMCO2 Systems Company](https://appshunter.io/developer/1683554220) | [CONON TECH PTY LTD](https://appshunter.io/developer/1723208775) |

## What reviewers say

### CO2 Filter Calc

[App page](https://appshunter.io/ios/app/co2-filter-calc/id6448122642)

**Features:** macOS Compatibility

**In-app purchases:** none


### BabalaVPN

[App page](https://appshunter.io/ios/app/babalavpn-fast-and-secure/id6475051277)

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly subscription | $3.99 | per 7 days |
| Monthly subscription | $12.99 | per month |
| Every 6 months subscription | $59.99 | per 6 months |
| Annual subscription | $89.99 | per year |


## Frequently asked questions

### Is CO2 Filter Calc free?

CO2 Filter Calc is free to download, with no in-app purchases.

### Is BabalaVPN free?

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

### Do CO2 Filter Calc or BabalaVPN have ads?

Neither CO2 Filter Calc nor BabalaVPN shows ads.

### Which is updated more often, CO2 Filter Calc or BabalaVPN?

CO2 Filter Calc ships an update weekly, and BabalaVPN every 9 days. Most recently, CO2 Filter Calc was updated on October 27, 2026 and BabalaVPN on October 27, 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.*