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.

** Not sure about buying this? Try our free RTA Lite! **

*** 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.

What's New

Version 9.0

-Upgraded for latest iOS and iOS devices
-Now supports iPhone X and other screens
-Bug fixes and stability improvements

Ratings and Reviews



Wow! Fixed.

It's nice to have such a good tool back working in a good way.

This really is a valuable tool for visualizing as you run live sound.

Thanks for fixing it.


Same as before. This app continues to run after you exit it and drains your battery. I cannot understand why, update after update, the developer continues to cling to this "feature". If you actually think that there is some use for this "feature", make it an option. I shouldn't have to stop the app before I exit it; this is not the iPhone paradigm and, as a result, users are likely to forget to do it. You hit home to exit the app, pocket your phone, and a few hours later discover this app still running and your battery low.


Same problem. This app continues to run after you exit the app and it drains your battery.


Same problem.


Yet another update that does not address the biggest -- well, only -- flaw in this app: it still continues to run after you exit it which drains your battery.


I wish the author would make the battery-draining background mode optional.


The author continues to tweak many aspects of this app, but it still keeps running after you exit it which drains your battery.


Same thing again. The author obviously likes to drain your battery.


New do-dadhs, but it still drains your battery if you're not watching.


Still has no way to turn off -- much less to default off -- the battery-draining background operation. Despite many updates, this app hasn't had a favorable review since 2013.


Another update and the battery-draining background operation continues. I really can't understand why this can't be made optional with the default being off.


With each new update, I hope that they will finally remove (or at least make optional) the battery-draining background mode. But, this latest update is unchanged in this respect.


New iPhone 6. Latest everything. Still drains the battery by continuing to run after you exit the ap.


Well, they did it again. Another update and the battery burn continues.


What can I say? The battery drain continues in yet another update. No wonder this is no longer the most popular RTA in the Apple store. When will the author fix this?


Another update and the drain continues.

Another update retains the battery-draining background operating feature. When you exit this app, it keeps running and sucking your battery. You have to manually kill it. This single "feature" just ruins this otherwise excellent app for me.


Yet Another update and it is clear that the developer feels that this battery-draining background feature is somehow desirable.

I have given up. Obviously, they do not read these comments because we have yet another update and the background battery drain remains. They obviously like this "feature."


I've been a huge fan of this app for years. I consider it essential for live- sound work.

But, recently, they added this "background" mode in which the app keeps running even when you exit it. To stop it, you have to manually kill it... a big and inconvenient extra step. And if you forget to kill it, it will run down your battery. When you're mixing a show, you don't want this extra step.

This silly "feature" is a disaster. I have complained and complained and yet this "feature" persists.

There are other Real Time Analyzer apps. If you are looking for one, despite how good this app is, I suggest you look elsewhere because of this one overwhelming problem.

Developer Response

To stop RTA from running in the background, just tap the Play/Pause button to stop the analysis. If this does not work for you, please contact us for support at --Andrew

Good, but FFT is better (I guess)


I was at work (I'm a live sound engineer) and we were discussing speaker phase, when I said "They should make an app so you could test spkrs with iPhone." It didn't take long before I found all the Studio 6 products. I now have SpeakerPop, GEN, SPL, & RTA. They all work wonderfully.
That said, I was a little disappointed to learn about FFT. It's not made too clear in the descriptions, but FFT is basically a more accurate & detailed version of RTA. I wish I'd bought FFT, since I want the most accurate thing availible. However, I'd already purchased RTA, & because of App Store rules, I can't trade it in towards FFT.
If you're going to spend $10 on an app, you are probably going to use it for work like me, so splurge & get the $20 FFT. I am debating it, my main hangup is that I've already spent $10 on the RTA app.

Suprisingly accurate.


I was hesitant to buy this app, thinking there was no way it could be remotely accurate. But since it was ten bucks, I figured it must be somewhat professional. So, I bought it, played with it a little, and then tested it against my analysis rig. I use smaart v.6 with a sound devices usbpre and an audix tr40a mic. I set up my rig and tested this app against it and was blown away by the results! It's very accurate considering the hardware it uses, and is a great app to have as a pocket rta. It's not as accurate or in-depth as smaart, but it's handy and is less than 1/100th the cost of my setup (not including the computer required to use it.) Overall, a great product. I have since bought studio six's tone gen and polarity check and am pleased with them as well.


Andrew Smith
22.9 MB
Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch.
English, French, German, Japanese, Polish, Simplified Chinese, Swedish
Age Rating
Rated 4+
© Andrew Smith
In-App Purchases
  1. Reference Curve Files $9.99
  2. STC -- Transmission Loss $9.99


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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