The air kiss is a ritual or social gesture whose meaning is basically the same as that of many forms of kissing. The air kiss is a pretence of kissing: the lips are pursed as if kissing, but without actually touching the other person's body. Sometimes, the air kiss includes touching cheek-to-cheek. Also, the gesture may be accompanied by the mwah sound. The onomatopoeic word mwah has already entered the Webster's dictionary.
In Indonesia, and Malaysia, it is common to air-kiss an elder's hand as a traditional form of respectful greeting. Instead of pursing one's lips, the younger person exhaling through his nose softly on the hand before drawing the hand to the younger person's forehead.
In the Philippines, elder relatives traditionally kiss a younger relative's cheek in this same way, by exhaling gently through the nose when the younger relative's cheek is brought close.