Comparison

SimpleFFT vs Rosetta

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

Head to head
About

SimpleFFT

Features
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This app can easily analyze the frequency of sound. For the sound of the recording file recorded at each refresh time interval, FFT is executed and displayed for the four voices collected one after another at each refresh interval.

About

Rosetta

Features
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Translate measurements instantly. A calm, ad-free unit converter for everyday checks — currency, weight, length, temperature, and ten more categories. Tap either side to make it the active value; both cards are first-class, so you can convert in either direction with one tap. Star up to ten favorites for one-tap reuse from the home screen. Currency rates come from the European Central Bank — cached after your first fetch, so they keep working offline. THIRTEEN CATEGORIES • Currency — 165 ISO currencies, ECB-sourced rates • Length — meters, feet, miles, kilometers, yards, inches • Mass — grams, kilograms, pounds, ounces, stones • Temperature — Celsius, Fahrenheit, Kelvin • Volume — liters, gallons, cups, fluid ounces, milliliters • Speed — m/s, km/h, mph, knots • Area — m², ft², acres, hectares • Time, Energy, Power, Pressure, Data, Angle WHY ROSETTA IS DIFFERENT • No ads. No tracking. No accounts. No analytics SDK ships in the app. • No settings to configure. The defaults are the right defaults. • Works offline. Currency rates cache after one online fetch; everything else needs no network at all. • Two-way input — convert in either direction with a single tap. • Tap any result to copy. A quiet "Copied" toast confirms. • Light and dark mode automatic, with locale-aware number formatting and gentle haptics. Free. Forever free. Made by Optiwise. Support: contact@optiwise.us Site: rosetta.optiwise.us

Screenshots

SimpleFFT4 screens
Rosetta4 screens

Verdict

The call

The clearest difference is in-app purchases: Rosetta at none against SimpleFFT's 1. Rosetta also leads on ads (none vs shown). On price, 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

Both are free to download. SimpleFFT sells 1 one-off in-app purchase. Rosetta asks for nothing beyond the download.

Scorecard2 real differences · 4 level
SimpleFFT versus Rosetta: the parameters behind the verdict, then further details
ParameterSimpleFFTRosetta
PriceFreeFree
Update frequencyEvery 18 months—
AdsYesNo — better
In-app purchasesYesNo — better
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.0 — better15.1
Further details — not scored
Size5 MB35 MB
Age rating4+4+
DeveloperHIROFUMI MARUOOptiwise

In-app purchases

1 purchases

SimpleFFT

One-time1
  • Premium Functions$0.49
None

Rosetta

No in-app purchases

Questions

Is SimpleFFT free?
SimpleFFT is free to download, with in-app purchases available.
Is Rosetta free?
Rosetta is free to download, with no in-app purchases.
Do SimpleFFT or Rosetta have ads?
SimpleFFT shows ads; Rosetta does not.

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