They are sometimes interchangeable and the use depends on the context, given that both frases are generally follow up questions: A: how are you? B: I'm pretty good. How about you? A: what have you been up to? B: I've been working a lot. what/how about you? (both work in this instance) https://english.stackexchange.com/questions/60632/what-about-you-versus-how-about-you

Hi, I would use HOW for a feeling: - I'm fine, how about you? (= HOW do you feel?) and WHAT for actions - I go dancing tonight, what about you? (= WHAT do you do tonight?) also for opinions PS -- I like it, what about you? (= WHAT do you think? )

I think generally the meaning of what and how in these sentences can be interchangeable. 'What about you' and 'How about you' both express interest in knowing someone's opinion/ the way someone is feeling. The difference may lie in the preceding part of the discourse, so that if someone starts with 'What' the logical consequence is using 'What' and if someone starts with 'How' the logical consequence is using 'How'. In spoken language these lines are obviously blurred and depend also on the habit of use of the speakers!

They are sometimes interchangeable and the use depends on the context, given that both frases are generally follow up questions: A: how are you? B: I'm pretty good. How about you? A: what have you been up to? B: I've been working a lot. what/how about you? (both work in this instance) https://english.stackexchange.com/questions/60632/what-about-you-versus-how-about-you

有差别吗？XD