It should work anywhere that accepts Visa debit. I’m not sure if there’s a currency conversion fee. More on reddit.com

It’s partly true, but it’s not specific to Apple Stores. Most (if not all) VISA and MasterCard credit cards in Canada have a limit of $250 for contactless purchases that’s set by the card issuer, regardless of whether the physical card or Apple Pay is used. This limit used to be $100 but was raised to $250 during the health pandemic. There’s nothing Apple or any other retailer can do about this, as the issuer controls this and will decline any tap transaction above $250. American Express does not have this limit as long as Apple Pay or another similarly authenticated digital wallet is used and the terminal can understand the difference between that and a physical card (the CDCVM protocol someone else mentioned). This is because AMEX doesn’t set any limits on digital wallet transactions. I’ve bought a MacBook with my AMEX through Apple Pay at the Apple Store and frequently tap for larger transactions at other merchants — as long as they support AMEX (sadly, Costco in Canada exclusively takes Mastercard, so there’s a $250 tap limit). If you’re visiting Canada and using a foreign card with Apple Pay, the limits will be based on your home bank. My U.S. VISA debit card has no special limits through Apple Pay either, and never has – I was using it in Canada with Apple Pay a year before Apple Pay was available from Canadian banks. Some retailers in Canada also have terminals that are programmed to not offer tap if the transaction exceeds $250. This is a terminal configuration issue, and has nothing to do with the card issuer or Apple Pay. In these cases, the terminal will refuse to even show tap as an option, so using Apple Pay will do nothing — you might as well be holding your iPhone up to a brick. The retailers generally do this to avoid confusion and delays from customers who try to tap and then cashiers who have to reset the terminal so they can try again, but it’s annoying for AMEX cardholders because it blocks us from using Apple Pay even though we otherwise could. More on reddit.com

Yes, but it will typically be called "Tap". More on reddit.com

In Canada, Apple Pay works anywhere tap works, you don’t need to look for specific Apple Pay logos. You can use it just about anywhere nowadays. I rarely need a physical card… fuel pumps and restaurants seem to be exceptions sometimes.

In other countries (eg USA), that’s not the case.

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