DAF Professional

Speechtools Ltd

About this app

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

DAF Pro is the best DAF app available for Android, has the lowest delay (latency) of all apps and also offers the choral effect.

We have measured the latency to be 20ms on Google Pixel phones but this will vary from device to device.

DAF Professional has been developed to be the leading app to help people who stutter / stammer or have Parkinson's Disease. It helps people to slow their rate of speech down which makes it sound clearer to others.

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 is the most effective and efficient Delayed Auditory Feedback (DAF) currently on the Android Market. No other app delivers the low latency required for effective use.

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 stutter / stammer, but has since been shown to work with people with other speech difficulties, such as those with Parkinson's 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 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 Parkinson's. 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.

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

If you encounter any problems then please email to [e-mail] and we will do our very best to help you.

Ratings and reviews

Poor. Can see it working, however crashes and hangs on a very modern phone and earpieces. Doesn't run in background, doesn't run when screen locked even with correct permissions. On android 13 on a Nothing phone.

The app is very good. However, I find that when I use bluetooth earbuds, the app keeps using the phone microphone. As a result, the volume is low, and I've found over the years that for DAF FAF to be effective you need high volume, not to hear the sound of your own voice. Personally, I would be more than willing to pay for a perfect FAF DAF app that manages to mask the sound of your voice and guarantees a more reliable experience, and I strongly encourage speechtools to add more tweaks.

I recently installed this paid version. But it has following bugs: 1) not working with phone calls with my realme 5i device with android version 10. 2) It uses mobile phone speaker instead of wireless Bluetooth earbuds. So what is happening, even though i am connected with Bluetooth earbud but if my phone is keeping far to me, it produces very slow voice sound as it is using mobiles speaker not headsets. Please fix these two issue, your app is really great, and very helpful to stuttering people

What's new

Fix working when screen is off on some devices