# Catheter vs AcidBase Calc

The clearest difference is price: AcidBase Calc at Free against Catheter's $0.99. AcidBase Calc also leads on iOS requirement (9.1 vs 17.0). On ads, in-app purchases and device support there is nothing between them.

AcidBase Calc is free to download; Catheter costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

## The numbers

| Metric | Catheter | AcidBase Calc |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 26 months | — |
| Size | 21 MB | 4 MB |
| Requires iOS | 17.0 | **9.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 12+ | 4+ |
| Developer | [Michael Buckner](https://appshunter.io/developer/746425887) | [Henry Ford Health System](https://appshunter.io/developer/393430586) |

## What reviewers say

### Catheter

[App page](https://appshunter.io/ios/app/catheter-patient-version/id796618275)

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

**In-app purchases:** none


### AcidBase Calc

[App page](https://appshunter.io/ios/app/acidbase-calc/id1477845851)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Catheter free?

Catheter costs $0.99, with no in-app purchases.

### Is AcidBase Calc free?

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

### Do Catheter or AcidBase Calc have ads?

Neither Catheter nor AcidBase Calc shows ads.

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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.*