Duct vs UnitConverter byNSDev
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Duct
This application simplifies the selection of duct sizes using intuitive design and simple operations. It calculates appropriate duct sizes based on airflow, standard static pressure, and air velocity, supporting both rectangular and round ducts.
- Intuitive design for easy duct size selection
- Calculates duct size based on airflow, static pressure, and velocity
- Supports both rectangular and round ducts
- Visual representation of selected duct shapes
- Customizable warning and upper limits for aspect ratio and air velocity
- Set default standard static pressure
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『Duct-Fit』は、直感的に分かりやすいデザインと単純な操作で、ダクトサイズを選定出来るアプリです。 「風量」「基準静圧」「風速」を基に適正なダクトサイズの算出が可能です。 特徴 ・選定したダクト形状を図形で表示することにより、ダクトイメージが付きやすい設計になっています。 ・「角ダクト」だけでなく「丸ダクト」のダクトサイズ算出にも対応してます。 ・「アスペクト比」や「風速」に目安となる「警告値」を任意で設定できます。 ・「アスペクト比」や「風速」に計算可能な上限としての「上限値」を任意で設定できます。 ・「基準静圧」は「初期値」として任意で通常使う値を設定することができます。 ・ダクトサイズの選定については、「コールブルックの式」及び「ダルシー・ワイズバッハ式」により、選定しております。
UnitConverter byNSDev
This tool converts between 26 different types of units, displaying conversion rates and allowing you to specify decimal places. It supports a vast array of units across categories like length, mass, volume, and more.
- Converts 26 types of units
- Displays conversion rates
- Customizable decimal places
- Supports numerous units in various categories
- User-submitted unit requests
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Tool to convert each of 26 types of units. When you select a unit of value that you enter, you create a table to calculate all the other units. It also displays the conversion rate. You can also specify the number of decimal places. 23 units in Length 18 units in Area 31 units in Volume 15 units in Mass 5 units in Angle 4 units in Temperature 7 units in Time 3 units in Frequency 5 units in Force 17 units in Pressure 6 units in Energy 6 units in Power rate 13 units in Speed 14 units in Acceleration 2 units in Dynamic viscosity 4 units in Kinematic viscosity 3 units in Magnetic flux density 2 units in Magnetic flux 7 units in Luminance 4 units in Illuminance 3 units in Radiation - source activity 2 units in Radiation - absorbed dose 2 units in Radiation - equivalent dose 2 units in Radiation - exposure 7 units in Infomation 7 units in Resolution Because we want to support units around the world, We will wait for the name and unit conversion information. Please enter your review.
Screenshots
Verdict
The clearest difference is review sentiment: Duct at 100% against UnitConverter byNSDev's 20%. Duct also leads on iOS requirement (11.4 vs 15.6). UnitConverter byNSDev's advantage is update cadence (every 5 months vs every 16 months). On price, ads, in-app purchases and monetization model there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Duct ships an update every 16 months, UnitConverter byNSDev every 5 months. The most recent releases landed on October 6, 2026 and October 4, 2026 respectively.
| Parameter | Duct | UnitConverter byNSDev |
|---|---|---|
| Price | Free | Free |
| Positive reviews | 100.0% of reviews — better | 20.0% of reviews |
| Update frequency | Every 16 months | Every 5 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 11.4 — better | 15.6 |
| Further details — not scored | ||
| Size | 3 MB | 4 MB |
| Age rating | 4+ | 4+ |
| Developer | Izumi Consulting,Inc. | NIHON SYSTEM DEVELOPER CORPORATION |
Customer experience
Duct
UnitConverter byNSDev
In-app purchases
Duct
No in-app purchases
UnitConverter byNSDev
No in-app purchases
Questions
Is Duct free?
Is UnitConverter byNSDev free?
Do Duct or UnitConverter byNSDev have ads?
Which is updated more often, Duct or UnitConverter byNSDev?
Other comparisons
