Comparison

Propeller Vibration vs String search calculator

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

Head to head

String search calculator

Free

🔧 Utilities

No ratingsView app →

About

Propeller Vibration

Read full description

Propeller vibrations will display a graph over your vibrations related to the propeller in your aircraft. Very useful for determining if a dynamic propeller balancing is required.

About

String search calculator

Features

Read full description

Displays the formula with the most frequent calculation result from the past calculation history. (Which formula is entered the most repeatedly)

Screenshots

Propeller Vibration3 screens

String search calculator1 screens

Verdict

The call

The clearest difference is price: String search calculator at Free against Propeller Vibration's $23.99. String search calculator also leads on update cadence (every 2 weeks vs every 43 months). Propeller Vibration's advantage is ads (none vs shown) and iOS requirement (12.0 vs 15.8.3). On in-app purchases and device support 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

String search calculator is free to download; Propeller Vibration costs $23.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Propeller Vibration ships an update every 43 months, String search calculator every 2 weeks. The most recent releases landed on May 29, 2026 and September 16, 2026 respectively.

Scorecard4 real differences · 2 level

Propeller Vibration versus String search calculator: the parameters behind the verdict, then further details
Parameter	Propeller Vibration	String search calculator
Price	$23.99	Free — better
Update frequency	Every 43 months	Every 2 weeks — better
Ads	No — better	Yes
In-app purchases	No	No
Devices	iPhone, iPad, iPod	iPhone, iPad, iPod
Requires iOS	12.0 — better	15.8.3
Further details — not scored
Size	9 MB	37 MB
Age rating	4+	4+
Developer	DOAO Consulting AB	Hideaki Uchikoshi

In-app purchases

None

Propeller Vibration

No in-app purchases

None

String search calculator

No in-app purchases

Questions

Is Propeller Vibration free?

Propeller Vibration costs $23.99, with no in-app purchases.

Is String search calculator free?

String search calculator is free to download, with no in-app purchases.

Do Propeller Vibration or String search calculator have ads?

String search calculator shows ads; Propeller Vibration does not.

Which is updated more often, Propeller Vibration or String search calculator?

Propeller Vibration ships an update every 43 months, and String search calculator every 2 weeks. Most recently, Propeller Vibration was updated on May 29, 2026 and String search calculator on September 16, 2026.