Both FluencyPal and SpeechEasy implement delayed auditory feedback (DAF). Both solutions are portable. However FluencyPal is a software application and thus offers a significantly more affordable solution as compared to the SpeechEasy or other hardware-based manufactured DAF devices. FluencyPal takes advantages of the increasingly powerful capabilities and features of the modern mobile phones, which also offer other general purposes such as voice calls, emails, Internet browsing – to name just a few. SpeechEasy and other DAF devices, on the other hand, must make its own micro-processor, which specifically designed to implement AAF, and thus are much more expensive.