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By Alex Wiltschko

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Fourier is an FFT for the iPhone! See the frequencies in sound around you in a gorgeous and snappy iOS 4-optimized app.

SINGLE TAP to see the peak frequency and musical note (you can use it as a tuner!)
DOUBLE TAP to pause the spectrum, to take a screenshot, or for more detailed analysis
TAP AND HOLD to bring up a cursor to inspect individual frequencies

What's New in Version 1.2.3

- Increased resolution
- Better default display regino
- Cursor works properly on retina display


iPhone Screenshot 1
iPhone Screenshot 2
iPad Screenshot 1
iPad Screenshot 2
iPad Screenshot 3

Customer Reviews

2x Resolution of Lite = 1/2 the size!

5 stars for real function, and 2 stars for bogus “resolution”. In terms of real function, just get Fourier Lite: you have to put up with ads at the bottom of the screen, but the read-out is easier to read. Both apps seem to the same, and they compare well with a pro grade sound/ noise frequency analyzer, I purchased the “real” one, to support the developer, and discovered that the promised increase in “resolution” is achieved by reducing the size of the sound graph. The Lite version is easier to read frequencies on.

Its perfect to me

I compared fourier with many other similar apps.
this app is very sensitive and has very fast signal response.
also its very easy to find howling frequencies.
but the only one bad thing is you need to double the frequency number of this app.
so its the best app to find howling frequencies very simply in indoor live concert.

Terrific App Except...

Except the Fourier graph horizontal scale is an octave off. You have to double the number.

For a single freq,unencrypted, you can use the numerical frequency at the top of the screen. It's correct.

View in iTunes
This app is designed for both iPhone and iPad
  • $4.99
  • Category: Music
  • Updated:
  • Version: 1.2.3
  • Size: 5.4 MB
  • Languages: English, Basque, Dutch, French, German, Japanese, Korean, Simplified Chinese, Vietnamese
  • Seller:

Compatibility: Requires iOS 5.0 or later. Compatible with iPhone, iPad, and iPod touch.

Customer Ratings

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