Two examples of intuitive devices are voice and gestures. Another is the pencil. While the pencil is remarkably simple to manufacture, it is extremely difficult to manufacture voice recognition and gesture recognition in any usable way.
Voice commands are still in the rudimentary stages.
However, they are being used in a limited way by pilots to help them carry out many tasks simultaneously. Glove input still has to be learned and is therefore not as intuitive as voice input. Also, one important area where much more development is needed is tactile feedback, without which there is no evidence of weight or object resistance. It is possibly more accurate for certain functions, particularly in areas such as virtual entertainment, than conventional input devices. The senses are a critical part of VR immersion.