# 龙嘉SCM供应商 vs Duct Calculator Pro

The clearest difference is price: 龙嘉SCM供应商 at Free against Duct Calculator Pro's $3.99. 龙嘉SCM供应商 also leads on update cadence (every 4 months vs every 72 months) and iOS requirement (12.0 vs 18.5). On ads, in-app purchases and device support there is nothing between them.

龙嘉SCM供应商 is free to download; Duct Calculator Pro costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

龙嘉SCM供应商 ships an update every 4 months, Duct Calculator Pro every 72 months. The most recent releases landed on October 4, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | 龙嘉SCM供应商 | Duct Calculator Pro |
| --- | --- | --- |
| Price | **Free** | $3.99 |
| Rating | — | **[1.0 (1 ratings)](https://appshunter.io/ios/app/duct-calculator-pro/id1492222891/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 72 months |
| Monetization | — | Paid |
| Size | 35 MB | 1 MB |
| Requires iOS | **12.0** | 18.5 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [文朗 梁](https://appshunter.io/developer/1293631579) | [Imran Pinjara](https://appshunter.io/developer/1484488781) |

## What reviewers say

### 龙嘉SCM供应商

[App page](https://appshunter.io/ios/app/scm/id1459545200)

**Features:** macOS Compatibility

**In-app purchases:** none


### Duct Calculator Pro

[App page](https://appshunter.io/ios/app/duct-calculator-pro/id1492222891)

This tool assists HVAC professionals and students with quick and precise calculations for duct sizing, airflow velocity, and airflow rate. It works offline and features a user-friendly interface for efficient project work.

**Highlights:** Duct size calculation, Airflow velocity (FPM) calculation, Airflow rate (CFM) calculation, Rectangular and round duct support, Offline functionality, Ad-free experience

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

**In-app purchases:** none


## Frequently asked questions

### Is 龙嘉SCM供应商 free?

龙嘉SCM供应商 is free to download, with no in-app purchases.

### Is Duct Calculator Pro free?

Duct Calculator Pro costs $3.99, with no in-app purchases.

### Do 龙嘉SCM供应商 or Duct Calculator Pro have ads?

Neither 龙嘉SCM供应商 nor Duct Calculator Pro shows ads.

### Which is updated more often, 龙嘉SCM供应商 or Duct Calculator Pro?

龙嘉SCM供应商 ships an update every 4 months, and Duct Calculator Pro every 72 months. Most recently, 龙嘉SCM供应商 was updated on October 4, 2026 and Duct Calculator Pro on October 25, 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.*