A Random Number Generator vs Wavelet Voice Sonogram
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
A Random Number Generator
Easily generate random numbers within a specified range. Simply select your desired minimum and maximum values, then tap the screen to get a randomized result. Perfect for quick decisions or games.
- User-defined number range
- Simple tap-to-randomize interface
- Easy to use
- Quick decision making tool
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This is a simple and easy to use number generator. Just choose the range and tap the screen to randomize.
Wavelet Voice Sonogram
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"Wavelet Voice Sonogram" is a sound spectrogram app that performs time-frequency analysis of acoustic signals. A spectrogram is a graph displaying the results of a sound frequency spectrum analysis, with time on the horizontal axis, frequency on the vertical axis, and signal strength represented by colors. This app can perform acoustic analysis and display the spectrograms by using three time-frequency analysis methods, Wavelet analysis, Octave Band analysis, and FFT analysis. It can also record sounds from iPhone's built-in microphone. While playing back a recording, you can search for the desired sound and analyze it. "Wavelet Voice Sonogram" makes it easy to analyze the acoustics of speech, instrumental sounds, noise, and more. It can also be used to learn the basics of speech analysis. Features: - Acoustic analysis can be performed using PCM data recorded with the iPhone's built-in microphone. It is possible to analyze 5 seconds of sound data backward from a user-specified point in time. - Three types of acoustic analysis, FFT analysis, octave band analysis and wavelet analysis, can be performed simultaneously. - PCM sound recording and playback is possible up to about 180 seconds, and the audio waveform graph and FFT analysis graph are displayed. While playing back sound, you can search for sound at any point in time. - Zoom in on a specific 10 seconds of PCM data and play back the sound. Used to find a specific sound at the point in time you want to analyze. - The spectrogram analysis result and time axis waveform can be contrasted and played back. Specifications: - Sampling frequency: 48 kHz - PCM recording time: approx. 180 seconds max. - Sound zoom function (10-Sec): Zooms in on any 10 seconds of PCM data and plays back the sound. - 3 types of acoustic analysis function (Analysis): About 5 seconds (Analysis points can be specified using the Time position slider.) -- FFT analysis (FFT): FFT 2048 points -- Octave band analysis (OCT): 1/48 octave band -- Wavelet analysis (DWT): Gabor Wavelet - Sound recording and playback, sound waveform and FFT graph display (Main): PCM graph, 10sec zoom graph, FFT graph. - Time position slider: Points to the cursor position on PCM graph. - Spectrogram display (FFT / OCT / DWT): 5 sec PCM graph and spectrogram analysis graph (vertical axis - time [0 - 5.0 sec], horizontal axis - frequency [100Hz - 8kHz]) - Snapshot (Snap): Save the analysis image in "Photos". Notes: - The acoustic analysis time varies significantly depending on the performance of your iPhone (product generation). It may take about 5 to 20 seconds. - Wireless (Bluetooth) headphones and headsets are not supported. - The first time the app accesses the built-in microphone and Photos after installation, the iOS system will ask you for permission to access them. If you have not enabled this setting, the application will not be able to access them due to iOS system privacy restrictions. Please enable the access permission in the iOS setting "Settings > Privacy & Security > Photos or Microphone". Please visit our iOS app support page for more information on this app.
Screenshots
Verdict
The clearest difference is update cadence: A Random Number Generator at weekly against Wavelet Voice Sonogram's every 8 months. A Random Number Generator also leads on price ($0.99 vs $6.99) and device support (3 vs 1). Wavelet Voice Sonogram's advantage is chart position (#151 vs unranked). On ads and in-app purchases 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
A Random Number Generator costs $0.99 and Wavelet Voice Sonogram $6.99 up front. Neither carries in-app purchases, so what you see is what you pay.
A Random Number Generator ships an update weekly, Wavelet Voice Sonogram every 8 months. The most recent releases landed on August 24, 2026 and September 26, 2026 respectively.
| Parameter | A Random Number Generator | Wavelet Voice Sonogram |
|---|---|---|
| Price | $0.99 — better | $6.99 |
| Rating | 4.9 (7 ratings) — better | — |
| Positive reviews | 80.0% of reviews | — |
| Number of ratings | 7 — better | — |
| Update frequency | Weekly — better | Every 8 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | — |
| Best chart rank | — | #151 — better |
| Devices | iPhone, iPad, iPod — better | iPhone |
| Requires iOS | 15.6 — better | 26.2 |
| Further details — not scored | ||
| Size | 3 MB | 0 MB |
| Age rating | 4+ | 4+ |
| Developer | Zero Pixels LLC | TOON,LLC |
In-app purchases
A Random Number Generator
No in-app purchases
Wavelet Voice Sonogram
No in-app purchases
Questions
Is A Random Number Generator free?
Is Wavelet Voice Sonogram free?
Do A Random Number Generator or Wavelet Voice Sonogram have ads?
Which is updated more often, A Random Number Generator or Wavelet Voice Sonogram?
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