In a patent filing titled “Audio User Interface for Computing Devices” the iPhone maker said that sometimes using the small screen on handheld devices can cause distractions from critical tasks such as driving and for others it may be difficult to use the small screen for regular everyday use . To end this problem, Apple recommends an audio user interface that generates audio prompts to help a user navigate through different features on the handheld devices. The audio prompt will help the user focus his attention on the critical task on hand. Apple also notes that using the handheld device for text-to-speech conversion gives poor results but if the system is used with a host computer and all the conversions are handled by the host computer the performance of such systems can be improved.

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