King of fruits in China is lychee.
King of fruits in India is mango.
King of fruits in Thailand is durian.
King of fruits in USA apple... as american as apple pie.
I guess 2.7 billion people can't be wrong...the first three make it to my list of top 5. I would also add longkong and white sapote. Honorary mentions to watermelon, cherimoya, biriba, mangosteen, apricot, peach, cherry.