Wow, native English speaker and I didn't even get the pun until this comment. I thought it was a stupid play on "What app should we message each other on?" and thus kind of a silly name. But folks use it regardless.
[1] https://www.youtube.com/watch?v=W16qzZ7J5YQ
(Forgive me, it was still recent around here at the time the app got popular).
I think whatsapp has a nice ring to it, even if people doesn't know how to write it. Surely being able to write it on a store search is important, but not as important as sounding good.
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And does people get the name of Waze? It took me a while, because in this case not being a native English speaker is a real problem.
Curious, because I'm pretty sure the first time I ran across Whatsapp it was in text, but I tend to 'hear' the things I read/write in my head, as though a voice read them to me. And because of that the pun stuck out. It might just be I'm more inclined to look for puns (playing games with them all the time with friends and family), but wondering if that might be part of it: if you just see the name and it's just a word, not something sounded out in your head, you of course would not notice the play on words.
And then there are the others [1].
1 https://twitter.com/KylePlantEmoji/status/122171379291396506...