This is the highly recommended and praised Function Generator App - an amazingly great and powerful tone generator. Enriched with a vast amount of features yet it is extremely intuitive and designed for simplicity.

Get to know this great App now! It is very well maintained and has received considerable upgrades over the past years.

So, … what can you do with this App?

• PLAY TEST TONES Sine, Rectangular, Triangular and Sawtooth.

• PLAY FREQUENCY SWEEP TEST TONES in both directions (minimum to maximum frequency and maximum to minimum frequency).

• PLAY VOLUME SWEEPS (from minimum to maximum volume).

• Try the SWEEP REPEAT / WOBBLE function.



• Or create your own CUSTOM PRESETS!

• And SAVE an endless amount of CONFIGURATIONS (Frequency, Sweep, Noise) for later quick access and direct playback function.

• Even play back different kinds of NOISE – White, Pink, Violet, Grey, Brown, Blue is also supported.

The Function Generator is AMAZINGLY INTUITIVE and SIMPLE!

=> Extending The Frequency Range
=> Extending The Sweep Times
=> Changing Min/Max Slider Frequency Ranges
=> Changing Max Sweep Time Slider Range
=> Changing Signal Amplitude
=> Enabling Of The Sweep Repeat / Wobble Function
=> Frequency Slider Setting to Linear or Logarithmic
=> Left/Right Channel Individual Selection
=> Permanently Saving Custom Presets
=> Saving Of Endless Number Of Audio Configurations
=> Phase Out Setting (custom phase shift of the generated signal)
=> BPM (Beats per Minute) Feature
=> Dual Function Generator
=> MultiTone Generator (playback of up to eight individual tones)
=> Click Track Generator
=> Background Theme Selection (Light/Dark)

Check out the new Tutorial page:

What’s New

Version 4.5.0

- new Click Track Generator! Now there is a new tool for generating click tracks that are super useful when measuring the latency in a multiroom setup. The click track itself is always 23ms long. The duration between the clicks can be fine-tuned between 23ms and 10 seconds.
- new "Play All / Play Sets" menu available for the MultiTone generator. Either play ALL tones at once. Or select individual tones per each of the available sets and play them separately.
- updated navigation menu. The settings menu is now integrated in the sidebar menu (top right burger button)! The bottom bar provides quick access to all the tools. And the sidebar menu provides access to Settings, About section, Tutorial and the rating button.
- native support for iPad 11"

Ratings and Reviews

4.7 out of 5
163 Ratings

163 Ratings

Siengtom ,

Best tool for an unusual problem.

Something was rattling in my car when playing music through my stereo. Problem was it would only rattle on certain bass notes and no song would create the rattle long enough for me to find it. It had driven me nuts for months!

I picked up a cassette adapter to pipe my iPhone audio into my car stereo. Then I purchased this awesome App and immediately pulled up the Musical Note menu. Starting at the bottom, I began stepping up the note scale until BAM! There it was! I was able to reproduce the rattle.

You won’t believe what I found. My spare garage door opener was vibrating inside my plastic glove box every time a bass guitar hit that note. From that moment, this Audio Function Generator from Thomas Gruber became worth 100 times what i paid for it. Thank You Tom! You rescued my driving sanity.

Recovering Gasaholic ,

Does just about everything I need

I love this app. I've been studying and using frequencies for over 10 years now. I finally found an app that not only let's me go beyond whole number to decimals, but also let's me type in the exact frequency I want to run. No inaccurate sliders to fiddle with here. I use it regularly. I love the new sets feature.

One thing I would like to see added is the ability to name the frequencies. I use different frequencies for different purposes. It would be nice to name Schumann Earth freq instead of having to memorize Earth is 7.83hz.

throckmeyer ,

helps with tinnitus?

I’ve been testing a new idea to reduce tinnitus, ie to listen to the pitch that matches the pitch i hear due to tinnitus. this app has easy to use features and good sound quality. i just wish it would run in the background so i can multitask while doing this therapy. i’ll let you know how well it works to reduce tinnitus. (the idea is the brain creates ringing in the ears to compensate for frequencies compromised due to damage to certain parts of the cochlea. if the auditory nerve can be stimulated at these frequencies, so the theory goes, maybe the brain will stop simulating them)

Developer Response ,

Hey there! The App already supports Audio Background Mode. Please just go to the settings page and enable "Continue playing audio in background". That will do the trick. cheers, -tom


Thomas Gruber
22.5 MB

Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch.


English, German

Age Rating
Rated 4+
© Thomas Gruber
In-App Purchases
  1. Enable all Features and Remove all Ads $2.99


  • Family Sharing

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

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