Comparison

DuctChecker vs PVVS

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

DuctChecker

Easily calculate duct dimensions using various engineering methods like constant pressure, static pressure regain, total pressure, and velocity. This tool simplifies complex duct design calculations, typically found in flow diagrams or slide rules.

Highlights
  • Constant pressure method calculation
  • Static pressure regain method
  • Total pressure method
  • Velocity method
  • Duct dimension determination
  • Simplified duct design
Features
Read full description

To determine the size of the duct constant pressure method, static pressure regain method, total pressure method, velocity method. Generally uses constant pressure method. This constant pressure method is how to determine the duct dimensions using the same value per 1 m on all duct friction loss. Usually determined by flow diagrams or duct design for slide rules. You can easily determine the duct by using this program.

About

PVVS

Features
Read full description

成型鏡板円筒胎による容噚の容積、衚面積、蚭定氎䜍における容量を求めるこずができるアプリです。 容噚の板厚ず玠材の比重を蚭定しお容噚の空重量を求めるこずもできたす。たた、溶接構造による容噚の堎合は3点のパヌツ䞊郚鏡板A,胎板L,䞋郚鏡板Bに分けお各郚毎に板厚、フランゞ長さを個別に蚭定し重量、容量を粟査できたす。 さらに、簡易匷床蚈算機胜もあり、蚭蚈圧力(内圧のみず䜿甚材料の蚱容匕匵応力蚭蚈枩床によるから蚈算板厚を求めるこずもできたす。 このアプリケヌション゜フトのご䜿甚は党お利甚者の自己責任においお行うものずしたす。 本アプリケヌション゜フトを運甚した結果生じた損害に぀いお、䜜者は䞀切の責任を負わないものずしたす。

Screenshots

DuctChecker3 screens
PVVS4 screens

Verdict

The call

The clearest difference is price: PVVS at Free against DuctChecker's $6.99. DuctChecker's advantage is ads (none vs shown). On update cadence, in-app purchases, device support and iOS requirement 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

CostPrice · In-app purchases · Ads · Monetization

PVVS is free to download; DuctChecker costs $6.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

DuctChecker ships an update every 4 months, PVVS every 2 months. The most recent releases landed on September 7, 2026 and September 8, 2026 respectively.

Scorecard2 real differences · 6 level
DuctChecker versus PVVS: the parameters behind the verdict, then further details
ParameterDuctCheckerPVVS
Price$6.99Free — better
Positive reviews0.0% of reviews—
Update frequencyEvery 4 monthsEvery 2 months — better
AdsNo — betterYes
In-app purchasesNoNo
MonetizationPaid—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.015.0
Further details — not scored
Size23 MB7 MB
Age rating4+4+
DeveloperAIR DESIGN, INC.sigeyosi kanenishi

In-app purchases

None

DuctChecker

No in-app purchases

None

PVVS

No in-app purchases

Questions

Is DuctChecker free?
DuctChecker costs $6.99, with no in-app purchases.
Is PVVS free?
PVVS is free to download, with no in-app purchases.
Do DuctChecker or PVVS have ads?
PVVS shows ads; DuctChecker does not.
Which is updated more often, DuctChecker or PVVS?
DuctChecker ships an update every 4 months, and PVVS every 2 months. Most recently, DuctChecker was updated on September 7, 2026 and PVVS on September 8, 2026.

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