In the recent times, interacting with machines has become instinctive. Moreover, the recent improvements in NUIs are guaranteeing that machines can understand human gestures, touch, words, and thoughts in a much better way. Even so, designing for Natural End user Interfaces is quite challenging as designers have to keep below parameters in mind.

SOUNDS SCI-FI NEVERTHELESS TIRING
Minority Report like office sounds really cool, but working with hands upward for a much longer period tire people. AJE should naturally and perfectly interact with the users without tiring them.

natural user cadre

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CAN'T AFFORD TO DISREGARD THE ACCESSIBILITY
Some actions might not be possible for users with afflictions. Therefore you can't do away with the support for assistive technology like Joysticks or electronic aiming devices.