# The B vs Ductulator

The clearest difference is review sentiment: The B at 100% against Ductulator's 50%. The B also leads on price (Free vs $3.99) and rating (5.0 vs 4.7). Ductulator's advantage is ads (none vs shown) and ratings volume (358 vs 4). On in-app purchases and device support there is nothing between them.

The B is free to download; Ductulator costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

The B holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Ductulator has 358 ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 100% of The B's written reviews are positive against 50% of Ductulator's.

The B ships an update every 9 months, Ductulator every 2 months. The most recent releases landed on October 24, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | The B | Ductulator |
| --- | --- | --- |
| Price | **Free** | $3.99 |
| Rating | **[5.0 (4 ratings)](https://appshunter.io/ios/app/the-b-y-app/id1434445476/reviews)** | [4.7 (358 ratings)](https://appshunter.io/ios/app/ductulator-duct-sizing/id1474939475/reviews) |
| Number of ratings | 4 | **358** |
| Positive reviews | **100.0% of reviews** | 50.0% of reviews |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 9 months | **Every 2 months** |
| Monetization | Ad-supported | **Free** |
| Best chart rank | — | **#51** |
| Size | 6 MB | 1 MB |
| Requires iOS | **15.0** | 18.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [The Behler-Young Company](https://appshunter.io/developer/1434445475) | [Wassim Murr](https://appshunter.io/developer/1474939474) |

## What reviewers say

### The B

[App page](https://appshunter.io/ios/app/the-b-y-app/id1434445476)

This app serves HVAC/R contractors with a comprehensive resource for products, expert support, and troubleshooting. It offers training, NATE testing, and field tools, representing hundreds of manufacturers across Michigan and Northwest Ohio.

**Highlights:** Vast product inventory, Expert support and troubleshooting, Contractor training, NATE testing, Field tools and calculators

**Features:** macOS Compatibility

**In-app purchases:** none


### Ductulator

[App page](https://appshunter.io/ios/app/ductulator-duct-sizing/id1474939475)

**Currently charting:** #51 Top Paid · Productivity (US App Store)

Instantly calculate HVAC duct sizes based on airflow, friction rate, or velocity. This tool provides accurate duct dimensions in seconds without needing charts, supporting various duct types and units.

**Highlights:** Instant duct sizing, Friction rate or velocity calculation, Multiple valid duct dimensions, IP and SI units support, Detailed sizing mode, Rectangular, circular, and flexible ducts

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

**In-app purchases:** none

**What reviewers like**

- 👍 Very helpful for duct sizing
- 👍 Easy to use in the field
- 👍 Saves time
- 👍 Seamless imperial/metric transitions
- 👍 Excellent tool for duct design

**What reviewers complain about**

- 👎 App should be free
- 👎 Functionality is pointless for some needs
- 👎 Doesn't help with traditional residential HVAC duct sizing
- 👎 App is a scam
- 👎 Decimal point doesn't work

**Reported bugs**

- Decimal point doesn't work on calculator
- New flex option isn't working properly
- Friction rate can't be changed in the latest version
- Skips duct sizes (e.g., 24-26)

**Requested features**

- Ability to pick duct size and see CFM
- Include flat oval ducts
- Option to select round or square duct
- Ability to enter duct size and get CFM
- Option for flex duct


## Frequently asked questions

### Is The B free?

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

### Is Ductulator free?

Ductulator costs $3.99, with no in-app purchases.

### Which has better reviews, The B or Ductulator?

The B is rated higher. The B averages 5.0 out of 5 from 4 ratings, while Ductulator averages 4.7 from 358 ratings.

### Do The B or Ductulator have ads?

The B shows ads; Ductulator does not.

### Which is updated more often, The B or Ductulator?

The B ships an update every 9 months, and Ductulator every 2 months. Most recently, The B was updated on October 24, 2026 and Ductulator on October 29, 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.*