# Calc pH vs Pressure Vessel Thickness

The clearest difference is price: Calc pH at Free against Pressure Vessel Thickness's $2.99. Calc pH also leads on iOS requirement (9.0 vs 16.1). On update cadence, ads, in-app purchases and device support there is nothing between them.

Calc pH is free to download; Pressure Vessel Thickness costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Calc pH ships an update every 59 months, Pressure Vessel Thickness every 56 months. The most recent releases landed on October 4, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | Calc pH | Pressure Vessel Thickness |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 59 months | **Every 56 months** |
| Monetization | — | Paid |
| Size | 0 MB | 1 MB |
| Requires iOS | **9.0** | 16.1 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | +4 |
| Developer | [ZOFTERM](https://appshunter.io/developer/557950548) | [Imran Pinjara](https://appshunter.io/developer/1484488781) |

## What reviewers say

### Calc pH

[App page](https://appshunter.io/ios/app/calc-ph/id566354963)

**Features:** macOS Compatibility

**In-app purchases:** none


### Pressure Vessel Thickness

[App page](https://appshunter.io/ios/app/pressure-vessel-thickness/id1492098075)

Calculate the required design and nominal thickness for various pressure vessel components according to ASME Section VIII Div 1 codes. This tool assists designers in determining the necessary thickness for shell, hemispherical, torispherical, ellipsoidal, and conical heads under internal pressure.

**Highlights:** Calculate design thickness, Calculate nominal thickness, Shell thickness calculation, Head thickness calculation (Hemi, Tori, Ellipsoidal), Cone thickness calculation, ASME Section VIII Div 1 compliance

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

**In-app purchases:** none


## Frequently asked questions

### Is Calc pH free?

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

### Is Pressure Vessel Thickness free?

Pressure Vessel Thickness costs $2.99, with no in-app purchases.

### Do Calc pH or Pressure Vessel Thickness have ads?

Neither Calc pH nor Pressure Vessel Thickness shows ads.

### Which is updated more often, Calc pH or Pressure Vessel Thickness?

Calc pH ships an update every 59 months, and Pressure Vessel Thickness every 56 months. Most recently, Calc pH was updated on October 4, 2026 and Pressure Vessel Thickness on October 17, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*