# CalcEngineer vs Psychro Calc Pro

The clearest difference is in-app purchases: CalcEngineer at none against Psychro Calc Pro's 2. CalcEngineer also leads on update cadence (every 2 days vs every 4 days). Psychro Calc Pro's advantage is iOS requirement (15.0 vs 17). On price, ads and device support there is nothing between them.

Both are free to download. Psychro Calc Pro sells 2 in-app purchases, starting at $3.99 per month. CalcEngineer asks for nothing beyond the download.

CalcEngineer ships an update every 2 days, Psychro Calc Pro every 4 days. The most recent releases landed on October 28, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | CalcEngineer | Psychro Calc Pro |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/calcengineer/id6748969344/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 2 days** | Every 4 days |
| Monetization | Free | — |
| Size | 10 MB | 23 MB |
| Requires iOS | 17 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 9+ | 4+ |
| Developer | [Justin Bush](https://appshunter.io/developer/1828308327) | [Mehmet Karakas](https://appshunter.io/developer/1886748581) |

## What reviewers say

### CalcEngineer

[App page](https://appshunter.io/ios/app/calcengineer/id6748969344)

This app provides professional engineering calculations for compressed air systems. It helps engineers and technicians determine CFM requirements, size compressors and tanks, and analyze pressure drops for optimized pneumatic systems.

**Highlights:** CFM Calculator, Compressor & Tank Sizing, Pressure Drop Analysis, Flow Velocity & Pipe Sizing, Multiple CFM Entries, General Engineering Calculator Suite

**Features:** macOS Compatibility

**In-app purchases:** none


### Psychro Calc Pro

[App page](https://appshunter.io/ios/app/psychro-calc-pro/id6760909140)

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Premium | $3.99 | per month |
| Lifetime Premium | $9.99 | one-time |


## Frequently asked questions

### Is CalcEngineer free?

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

### Is Psychro Calc Pro free?

Psychro Calc Pro is free to download, with in-app purchases available.

### Do CalcEngineer or Psychro Calc Pro have ads?

Neither CalcEngineer nor Psychro Calc Pro shows ads.

### Which is updated more often, CalcEngineer or Psychro Calc Pro?

CalcEngineer ships an update every 2 days, and Psychro Calc Pro every 4 days. Most recently, CalcEngineer was updated on October 28, 2026 and Psychro Calc Pro on October 31, 2026.

---

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