Does it cost any fee to transfer money from my bank account to Apple Saving in iPhone?

I recently opened an Apple Savings account. I would like to transfer money to apple savings account with an attractive APR. I want to top up my Apple Savings account with money from my bank account through Wallet on my iPhone. However, I am curious if Apple or my bank will charge any fee in this process. And how long will it take to top up?

Thanks. :)