Such technology could fix one of the biggest complaints of the iPhone's virtual keyboard, which is the lack of any non-visual response. The haptic response could be in the form of a vibration and paired with an audible noise, the document filed with the U.S. Patent & Trademark Office says.

Besides the use on virtual keyboards, the tactile feedback would also be useful for scrolling around virtual click wheels, sliding a finger across a trackpad, or touching a multi-touch display screen, the patent application said.

Such non-visual cues would be useful to touchscreen users who are visually impaired or are using their electronics in the dark. The technology would also be useful when a person's attention is diverted, such as when driving a car, which is not uncommon, and not recommended.

Apple on Thursday also submitted two other patent applications, one for technology to detect fingerprints and the other for a radio-frequency identification reader.

The fingerprint detector would make it possible for a person to initiate commands on a device through the use of a particular finger. For example, the system could detect the unique fingerprint on the middle finger to play music, or the touch of a person's pinky could fast-forward or rewind music. The variety of commands could be increased by launching functionality by double tapping with a particular finger.

The RFID-related patent would involve placing an antenna in the touchscreen of a device for reading RFID tags. Such tags are mostly used for tracking and managing inventory in a supply chain. The technology is expected to be more widely used in the future.

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