# IAPMO Codes vs HVAC Know It All

The clearest difference is review sentiment: HVAC Know It All at 84% against IAPMO Codes's 0%. HVAC Know It All also leads on rating (4.8 vs 3.8) and ratings volume (221 vs 6). IAPMO Codes's advantage is in-app purchases (none vs 2) and device support (3 vs 1). On price, update cadence and ads there is nothing between them.

Both are free to download. HVAC Know It All sells 2 in-app purchases, starting at $0.99 per month. IAPMO Codes asks for nothing beyond the download.

HVAC Know It All holds the better App Store score, 4.8 against 3.8. That said, the two scores are not equally well evidenced: HVAC Know It All has 221 ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 0% of IAPMO Codes's written reviews are positive against 84% of HVAC Know It All's.

IAPMO Codes ships an update every 7 months, HVAC Know It All every 6 months. The most recent releases landed on June 1, 2026 and September 17, 2026 respectively.

## The numbers

| Metric | IAPMO Codes | HVAC Know It All |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.8 (6 ratings)](https://appshunter.io/ios/app/iapmo-codes/id1457481184/reviews) | **[4.8 (221 ratings)](https://appshunter.io/ios/app/hvac-know-it-all/id1548260016/reviews)** |
| Number of ratings | 6 | **221** |
| Positive reviews | 0.0% of reviews | **83.7% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 6 months** |
| Monetization | **Free** | Subscription |
| Size | 22 MB | 67 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [International Association of Plumbing and Mechanical Officials](https://appshunter.io/developer/1455422752) | [HVAC Know It All Inc.](https://appshunter.io/developer/1548260018) |

## What reviewers say

### IAPMO Codes

[App page](https://appshunter.io/ios/app/iapmo-codes/id1457481184)

Access and manage your purchased IAPMO codes, including the UPC, UMC, and others. Make annotations, record voice notes, and view content offline. Stay informed with code errata, committee information, and breaking news.

**Highlights:** View purchased IAPMO codes, Offline access, Make annotations, Voice recordings, Access code errata, View development timeline, Direct access to engineering staff

**Features:** macOS Compatibility

**In-app purchases:** none


### HVAC Know It All

[App page](https://appshunter.io/ios/app/hvac-know-it-all/id1548260016)

Connect with HVAC/R professionals to enhance your skills through educational discussions. This app aims to help technicians, installers, owners, educators, and students improve their expertise in the trade.

**Highlights:** Educational discussions, Professional networking, Skill enhancement, Trade knowledge sharing, Technician resources

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $0.99 | per month |
| Yearly Subscription | $9.99 | per year |

**What reviewers like**

- 👍 Excellent community for tradespeople
- 💡 Vast knowledge sharing among professionals
- 🚀 Game-changer for HVAC technicians
- 🤝 Supportive and non-judgmental environment
- 📚 Great resource for learning and growth

**What reviewers complain about**

- 💰 Forced to pay before accessing content
- 🤔 Subscription fee not clearly stated upfront
- 🚫 App makes you pay before you can test it
- 📉 Limited content in residential group
- ❓ Suspect 5-star reviews, potentially fake

**Requested features**

- More content for the residential group


## Frequently asked questions

### Is IAPMO Codes free?

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

### Is HVAC Know It All free?

HVAC Know It All is free to download, with in-app purchases available.

### Which has better reviews, IAPMO Codes or HVAC Know It All?

HVAC Know It All is rated higher. IAPMO Codes averages 3.8 out of 5 from 6 ratings, while HVAC Know It All averages 4.8 from 221 ratings.

### Do IAPMO Codes or HVAC Know It All have ads?

Neither IAPMO Codes nor HVAC Know It All shows ads.

### Which is updated more often, IAPMO Codes or HVAC Know It All?

IAPMO Codes ships an update every 7 months, and HVAC Know It All every 6 months. Most recently, IAPMO Codes was updated on June 1, 2026 and HVAC Know It All on September 17, 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.*