Apple released their Apple Cards to the general public on August 21, 2019. I applied that day. The process was very easy. You open the Wallet app and press the plus sign in the upper right corner. You are taken to an Apple Pay screen and you tap the blue continue button. There you will see a link to sign up for the Apple Card. You enter in some information about your annual income and other personal info and then it presents you with an offer for an APR interest rate based on your credit score. Mine was 17.99%. Here you can either accept or deny the card. I accepted and it took a few minutes to process and then the card was in my virtual wallet. I also ordered the physical titanium card (we now know it 90% titanium and 10% aluminum) which arrived a week or two later. The card arrived in a nice cardboard thin box which must have had a NFC chip in it because to activate the card, all you do is tap a section of the box.
Using the card has been pretty painless. I am now using this card for Amazon purchases and you find the card number, expiration date, and 3 digit code by tapping the three dots next to the card and then Card Information. It then prompts you for Touch ID or Face ID before showing you the card numbers. I also use the card for iTunes and will when I buy a new iPhone in October. For Apple purchases you get 3% cash back, Apple Pay purchases are 2% cash back, and everything else is 1% cash back. I have used the physical card in a couple locations like HEB (still no Apple Pay in San Antonio) and Pizza Hut.
In order to pay off the credit card, you enter you bank routing and account numbers in the Wallet app. The card in the app changes colors when you buy stuff and then turns white when you pay it off. There is a wheel that you can turn to adjust how much you would like to pay off. You also get a list of all your transactions and notifications for how much cash back you get every day. The cash back is applied to your Apple Pay Cash which you can then transfer to your bank or use toward iTunes purchases.
The last thing to mention is to opt out of arbitration. You might want to opt out of arbitration in order to keep your right to sue or participate in a class action if something goes wrong. More information can be found here. Everything has been really easy on this card from applying to using to paying off. It is also nice only having my name and nothing else on the physical card for security purposes.