After upgrade to iOS 8.0.2, Yahoo mail push does not work any more for me. I deleted and added back the account, power cycled the phone, nothing helped. iCould push works. I use Apple mail app. It used to work fine with iOS 7. Interestingly, my first generation iPad with iOS 5.1.1 also stopped Yahoo mail push suddenly. That tells me the problem may be on Yahoo server as well.
I read lots of such issues with Exchange server. I also read there were push notification API changes in iOS 8. A friend with similar phone and iOS 8 has Yahoo push notification working sometimes, but not always.
Wherever the problem is, I hope Apple and Yahoo get together to fix the problem.
The Yahoo mail app works for push with iOS 8.
