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DAF Pro: Stuttering,Stammering app for iPhone and iPad


4.2 ( 32 ratings )
Utilities Medical
Developer: Speechtools Ltd
4.99 USD
Current version: 3.3.2, last update: 1 year ago
First release : 04 Jan 2012
App size: 22.87 Mb

* The worlds number 1 DAF app is used by thousands of people in over one hundred countries. *

DAF Professional has been created to help people who stammer or have a neurological disease such as Parkinsons Disease. It helps people to slow their rate of speech which makes it clearer to others.

DAF Professional is an easy to use professional speech therapy tool which could make a huge difference to you or someone you know.

DAF Professional has been designed and tested by a certified and practicing Speech and Language Therapist (MSc, PGDip, BAHons, HPC registered and member of RCSLT). DAF Professional delivers incredibly low latency feedback even when running in the background.

Delayed Auditory Feedback (DAF) is a well established speech and language therapy tool which helps people to speak more slowly. However, until recently, devices have been cumbersome to carry around, difficult to adjust, very expensive and therefore not widely used.

DAF was originally developed for people who stammer, but has since been shown to work with people with other speech difficulties, such as those with Parkinsons Disease (Downie et al., 1981; Dagenaise, Outhwood & Lee, 1998; Lowit et al., 2006 and most recentely Lowit et al., 2010).

It works by enabling someone to hear his or her own speech in an altered manner. This disruption to the normal auditory feedback loop causes the speaker to slow down. Research has shown that DAF will be of benefit to approximately a third of people who have a stammer or Parkinsons. Clinical research has not been carried out as yet on other client groups however DAF may well be of benefit to people with other medical speech conditions.

When using Bluetooth devices there is an additional delay of 60ms added to the feedback system.

If you do use a Bluetooth headset you may find you need to turn the bluetooth device on after opening the app to enable it.

DAF Professional works when put in the background or the screen is turned off. Like all apps of this type, it can NOT work during phone calls or with other media apps playing at the same time.

If you wish to provide any feedback we would be delighted to hear from you. Please email us at [email protected].

Our lead Speech and Language Therapist is Samantha Brady who qualified as a Speech and Language Therapist in 2001 (PGDip, City University) and gained her Masters in Speech and Language Therapy in 2006 (MSc, City University). She has a wealth of experience of working as a Speech and Language Therapist in a variety of settings and her area of clinical expertise is adult neurology and voice. Samantha is a member of the Royal College of Speech and Language Therapists (RCSLT), HPC Registered (SL10250) and Lee Silverman Voice Treatment Certified (LSVT).

DAF Professional is fully GDPR compliant and will not collect any of your data without first asking for your consent.

Pros and cons of DAF Pro: Stuttering,Stammering app for iPhone and iPad

DAF Pro: Stuttering,Stammering app good for

I was impressed with how the microphone automatically shuts off when your not talking so you dont hear background noise. Better than most DAF apps
It did improve stuttering, and would be perfect if was accessible during phone call in iPhone

Some bad moments

Finally a daf tool that all stutterers can use via the iOS platform! Its free. The voice the stutterer hears is their own voice, very natural, not robotic as previous devices have been. I tried it for first time today with a high school senior who stutters pretty severely. It worked perfectly! He was 100% fluent, first time, reading aloud. Incredible experience for him and me! I am an SLP
This app has been extremely helpful when working with my stuttering clients. Im still trying to figure out how to work it on my iPad but it works great on my iPhone!
DAF Pro is elegant and amazing! After a little experimenting with the amount of delay, I have some wonderful results. The app also runs in the background, so you can keep it running while you use other apps like email and web. Thanks for this amazing tool!
I have no use for it, but I use it as an amplifier. My mic built into my Sony earbuds with volume control is sensitive, so i use it As an amplifier for my bad hearing. Delay all the way down, volume up on system and app, and there ya go!
This amazing device has given me the confidence to speak out when I have too shy to before. It makes presentations, and reading outloud.
I have been using this app for a few months and now it is not working at all ( on both my iPad and iPhone). Please fix! It was great for my students who stutter.