Comparison

DAF Delayed Auditory Feedback vs The Speech Jammer

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

DAF Delayed Auditory Feedback

This app uses delayed auditory feedback to make speaking difficult by playing your voice back through headphones with a slight delay. It's a tool for psychological experiments, allowing users to test the effects of DAF on their own speech.

Highlights
  • Delayed auditory feedback simulation
  • Voice input via microphone
  • Audio output through headphones
  • Psychological experiment tool
  • Adjustable delay effects
  • Speech disruption testing
Features
Read full description

Try saying "toy boat" repeatedly. It's hard to say, right? There are many words like this, and if you have to use them during an important presentation, it can be quite stressful. But with this app, "toy boat" becomes... **Hugely** difficult to say. If you thought, "Wait, shouldn't it make it easier to say?" you're wrong. It really becomes **hugely** difficult to say. This is a "who benefits from this?" kind of app. What this app does is simple. It picks up your voice through the microphone and plays it back through the headphones (or earphones) with a slight delay. That's all it does. This simple process is called Delayed Auditory Feedback, or DAF for short. DAF is known to have interesting effects. It makes it difficult to speak. So, the already difficult "toy boat" becomes **hugely** difficult to say with DAF. This might seem like a "who benefits from this?" kind of thing, but it's a very interesting phenomenon from a cognitive psychology perspective. Also, DAF doesn't always make speech difficult; the extent of the disruption varies depending on the amount of delay and the way you speak. This app is a simple psychological experiment tool that allows you to test when DAF's effects are most pronounced using yourself as the subject. Experiment with different scenarios using "toy boat" as the keyword. **Important** When using this app, you must have headphones (or earphones) with a microphone. You cannot substitute the device's built-in microphone and speakers. I'll say it again. You cannot substitute the device's built-in microphone and speakers. **Warning** DAF creates a speech situation different from normal. It is possible that this may cause some stress to your mind and body. We cannot take any responsibility for any issues that arise from using this app. Please understand the principles of DAF fully and use this app at your own risk. If you feel any abnormalities in your mind or body, stop using the app immediately. Additionally, we do not recommend letting minors, especially young children, experience DAF. **Effect on Stuttering** There are reports that DAF has improved stuttering. However, this app was developed purely as a simple psychological experiment tool to examine how DAF affects the speech of non-stutterers from a cognitive psychology perspective.

About

The Speech Jammer

Features
Read full description

The Speech Jammer slightly reduces the rate at which you hear your voice, making it very difficult to talk. • Adjustable delay to impair speech • Stories to make it even more difficult • Turkish, Spanish, English, French, Portuguese, German, Korean, Russian, Arabic, Hindi languages.

Screenshots

DAF Delayed Auditory Feedback1 screens
The Speech Jammer3 screens

Verdict

The call

The clearest difference is ads: The Speech Jammer at none against DAF Delayed Auditory Feedback's shown. The Speech Jammer also leads on update cadence (every 2 months vs every 6 months) and iOS requirement (11.0 vs 15.0). On price, in-app purchases and device support 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

DAF Delayed Auditory Feedback ships an update every 6 months, The Speech Jammer every 2 months. Both last shipped on September 11, 2026.

Scorecard3 real differences · 7 level
DAF Delayed Auditory Feedback versus The Speech Jammer: the parameters behind the verdict, then further details
ParameterDAF Delayed Auditory FeedbackThe Speech Jammer
PriceFreeFree
Rating2.3 (6 ratings) — better—
Positive reviews20.0% of reviews—
Number of ratings6 — better—
Update frequencyEvery 6 monthsEvery 2 months — better
AdsYesNo — better
In-app purchasesNoNo
MonetizationAd-supported—
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS15.011.0 — better
Further details — not scored
Size5 MB30 MB
Age rating12+4+
DeveloperJunichiro SeyamaCENK YILDIRIM

In-app purchases

None

DAF Delayed Auditory Feedback

No in-app purchases

None

The Speech Jammer

No in-app purchases

Questions

Is DAF Delayed Auditory Feedback free?
DAF Delayed Auditory Feedback is free to download, with no in-app purchases.
Is The Speech Jammer free?
The Speech Jammer is free to download, with no in-app purchases.
Do DAF Delayed Auditory Feedback or The Speech Jammer have ads?
DAF Delayed Auditory Feedback shows ads; The Speech Jammer does not.
Which is updated more often, DAF Delayed Auditory Feedback or The Speech Jammer?
DAF Delayed Auditory Feedback ships an update every 6 months, and The Speech Jammer every 2 months. Most recently, DAF Delayed Auditory Feedback was updated on September 11, 2026 and The Speech Jammer on September 11, 2026.

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