What's the difference between "What about you" and "How about you"?
I often wonder which one to use when I'm talking with others.
For example:
A:How are you?
B:I'm great. What about you( or How about you?)
And I will appreciate it very much if you can give me some other examples to show the difference between these two sentences.

Question

What's the difference between "What about you" and "How about you"?
I often wonder which one to use when I'm talking with others.
For example: 
A:How are you?
B:I'm great. What about you( or How about you?)
And I will appreciate it very much if you can give me some other examples to show the difference between these two sentences.

Answer

Hi, these questions have the same meaning. It's your choice. This also applies in other contexts, for example :
Do you want to go out for dinner tonight? 
Sure, what time? 
What/how about 7pm?