RTA vs iAudioTool
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
RTA
Analyze audio frequencies, test speakers, and tune rooms with this professional-grade acoustical analysis tool. It offers octave and 1/3 octave modes, peak hold, and averaging, with automatic microphone compensation for accurate results.
- Real-time acoustical analysis
- Octave and 1/3 Octave modes
- Peak Hold and Average modes
- Automatic microphone compensation
- Save, recall, and export graphs
- Interactive touch GUI
- Noise curve overlays
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A Real Time Analyzer for the iPhone, iPad and iPod Touch. Test your speakers, tune your room, do acoustical analysis work or just have a better understanding of audio frequencies. RTA is a professional-grade acoustical analysis tool. All filters meet or exceed ANSI and IEC Class 1 specifications. Includes Octave and 1/3 Octave modes, with selectable decay times, as well as Peak Hold and true linear Average mode. *** iOS Microphones We have analyzied every iOS device, including all of the iPads, all iPhones, and iPod touches, and have created microphone compensation files that are applied automatically. You can trust the results you are getting, often within just a few dB of a far more expensive analyzer. Calibration is updated regularly, automatically, from our cloud-based calibration database. Upgrade to our iTestMic or iAudioInterface2 to bring your system up to full professional specs. *** Save and Recall Graphs You can save and recall graphs, marked with the GPS location, date & time, and your comment, as well as store the image to your photo roll. Export the data as an XLS formatted file to your computer for inclusion in reports or further analysis. *** Max and Min Bars You can also turn on resettable Max/Min bars (see image #4) to capture peaks. Double-tap to reset the bars. *** Specifications and Devices The internal iPhone mic has a noise floor near 30 dB, and if your are running iOS 6, clips around 120 dB. *** Touch GUI Fully interactive touch GUI features includes scroll up/down, pinch to zoom or compress the vertical dB scale, or swipe horizontally to get a cursor that reads out the exact dB level and frequency across the screen. To make the cursor disappear, swipe it off the graph to the left. The landscape-mode display flips 180 degrees so that you can face the internal mic in either direction. *** Overlay Curves Also included are optional noise curve overlays, in NCB, RC, PNC, NC, X-Curve and NR mode. See picture #2 for an example. Use this feature to get a quick reading on the noise levels in a room. Also includes the cinema large-room X-curve overlay. *** Calibration RTA can be fully calibrated, whether you are using it with the internal iOS microphone, or one of our professional test & measurement mic solutions. And, if you are using iTestMic, the mic calibration is transmitted directly to the app, so you are always calibrated. *** RTA or FFT? If you are wondering if you should download this app or our FFT app, check out our website, we have a page devoted to this topic. See our other acoustics and audio apps, including AudioTools.
iAudioTool
This app provides advanced audio analysis tools for professionals and enthusiasts. It includes features like RT60, SPL metering, spectrum analysis, and signal generation to help you understand and optimize sound environments. Calibration features ensure accurate measurements for various audio applications.
- RT60 measurement
- SPL meter
- Spectrum analyzer
- Signal generator
- Polarity checker
- ISO Octave Calibration
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Room Reverberation (RT60), SPL (dB) Meter, Spectrum Analyzer, Signal Generator, Polarity Checker. Features 1/1, 1/3 & 1/6 octave RTA modes, Leq, RT60 (wideband, and Octave), spectrogram, peak frequency, Fast, Medium & Slow filters, Flat & A/C Weighting, Averaging, SPL Chart Recorder, Noise Criteria (NC), White/Pink Noise, Sine, Square, Triangle, Sweep, Ramp and Impulse signals & loudspeaker polarity checker. Frequency spectrum store & load, RT60 store, and Chart store. Stored files can be sent as Email. Includes ISO Octave Calibration feature - corrects for your device's microphone response. Also includes wideband calibration. The calibration discs are moved up or down so as to obtain a flat response, and match the overall SPL to that of an external meter. Use: home theater, audio engineer, car audio, etc Online manual at: https://sites.google.com/site/bofinit/iaudiotool Please join the AudioTool Discussion Group to request features or report problems: http://groups.google.com/group/audiotool-discussion-group AudioTools's Spectrum Analyzer component uses FFT on batches of samples recorded at the microphone. Hann windowing reduces aliasing. Recorded spectra may be stored as files in the device memory, and then loaded later and displayed together with the live spectrum. The "Store" button will store the current live spectrum. The "Load" button brings up a list of stored spectra. One of these can be chosen, or the "Cancel" item selected to return to the main display, or the "Clear" item selected to remove the currently loaded spectrum. Data collection can be paused and restarted. The deciBel meter component uses IIR filters and exponential averaging to calculate Flat, A and C weighted response at speeds of Fast, Medium and Slow. A pair of cursors can be shown on the RTA and Chart Recorder displays: each can be moved to any position, and will display the SPL & time/frequency values measured there. Initially, both cursors are positioned mid-screen - simply drag them to a new position with the fingertip. The cursors can be turned on and off in the Menu. The loudspeaker polarity checker can be used to check whether a loudspeaker is wired in phase: connect the AudioTool output to the speaker under test, select "Polarity" from the signal generator screen, then return to the RTA screen. If the speaker is out of phase (polarity reversed) AudioTool will show "Pol ---", otherwise "Pol +++" if the speaker is in phase. The Noise Criteria (available from the Menu) function shows a set of NC contours overlaid on the 1/1 Octave RTA display and the calculated real time current NC value is also shown. The Chart Recorder shows a moving trace of the SPL measurements over the last few minutes. Reverberation (RT60) measurements can be made by starting the RT60 component and using a loud clap (or similar) to trigger the measurement. RT60 times measure how much reverberation or echo there is in a room or auditorium. The Signal Generator generates White and Pink Noise, Sine, Square, Triangle and Ramp waves, and Impulses. The generator uses multiple cycled buffers that are refreshed randomly so ensuring truly random White/Pink noise. The Pink Noise algorithm uses Kemmet's method to adjust White Noise into Pink. Sine/Square/Ramp/Triangle Frequency can be set via the arrow buttons or directly entered using the keyboard. The Impulse signal is a delta, issued approximately once per second. The accuracy in frequency of the generated periodic signals is quite good: on the iPad, errors were of the order of 1% throughout most of the range. Sine wave fidelity is good throughout most of the audio range. Other signals' leading and trailing edges show ringing and decreasing frequency response artefacts in the upper ranges. Disclaimer: iAudioTool's performance depends on the iPad/iPhone hardware, and is not guaranteed to meet any audio measurement or safety standards.
Screenshots
Verdict
The clearest difference is rating: RTA at 3.9 against iAudioTool's 3.3. RTA also leads on review sentiment (61% vs 34%) and chart position (#134 vs unranked). iAudioTool's advantage is in-app purchases (none vs 2) and update cadence (every 2 months vs every 3 months). On ratings volume, ads, 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
RTA costs $4.99 and iAudioTool $2.99 up front. RTA sells 2 one-off in-app purchases. iAudioTool asks for nothing beyond the download.
RTA holds the better App Store score, 3.9 against 3.3. Both are backed by a comparable volume of ratings — 26 and 13 respectively. Written reviews point the same way: 61% of RTA's written reviews are positive against 34% of iAudioTool's.
RTA ships an update every 3 months, iAudioTool every 2 months. The most recent releases landed on October 17, 2026 and October 15, 2026 respectively.
| Parameter | RTA | iAudioTool |
|---|---|---|
| Price | $4.99 | $2.99 — better |
| Rating | 3.9 (26 ratings) — better | 3.3 (13 ratings) |
| Positive reviews | 60.7% of reviews — better | 34.5% of reviews |
| Number of ratings | 26 — better | 13 |
| Update frequency | Every 3 months | Every 2 months — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases — better | Paid |
| Best chart rank | #134 — better | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 15.0 — better | 16.0 |
| Further details — not scored | ||
| Size | 29 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | Andrew Smith | Julian Bunn |
Customer experience
RTA
iAudioTool
Bugs and requests
RTA
Reported bugs
18 issues- App crashes after iOS updates (iOS 13, 15, 16, 17, 18)
- App freezes or crashes on startup
- App only displays half the screen
- App does not save analysis readings to photo roll
- App stops working on older iPads after updates
Show 13 moreShow fewer
- Accessory found/removed loop with iTestMic 2
- App continues to run in background, draining battery
- Calibration not supported for specific iPad models
- App not installing after purchase/update
- App not opening on iPhone 4 after update
- dB/input level is useless after update
- Screen not expanding after updates
- App not compatible with iOS 7
- App crashes when saving screen
- App not working with iMM-6 microphone
- App overcompensates for low frequencies
- App crashes on 3G S after update
- Low frequency response cut due to voice recognition
Requested features
8 requests- Add German language support
- Add NC and NR curves
- Make background mode optional
- Improve compatibility with newer iOS versions
- Add option to overlay readings
Show 3 moreShow fewer
- Add zoom functionality for frequencies
- Improve calibration for external mics
- Add pink noise output
iAudioTool
Not enough reviews yet to summarise bugs or requests.
In-app purchases
RTA
- STC -- Transmission Loss$9.99
- Reference Curve Files$9.99
iAudioTool
No in-app purchases







