This App, called the DAF Assistant, can be used by people who stutter to control their speech fluency, slow down speech rate and increase confidence level. It is available for $12.99 on iTunes.
The impact of Delayed Auditory Feedback on stuttering was depicted in the movie the King's Speech. It's effectiveness depends on the situation and the individual. It is based on the same principle as the SpeechEasy device.
Please note that the use of DAF to control stuttering is not a treatment, as the effects are not present when not using the device. It is recommended that it be used in conjunction with speech therapy techniques.
To use the DAF Assistant application you will need "Apple Earphones with Remote and Mic" headset which is available in Apple Store. On iPhone you can also use Bluetooth headset. The application is compatible with iPhone, iPod Touch, and iPad.