I've now been a long term user of both Android and Samsung Pay. I've also used banking apps with built in contactless pay like Barclays Pay and Amex Pay.
The latter all work flawlessly, but of course are really limited in features, so a bit pointless really.
I have noticed that with Android Pay, if I use a card not taken by the store I'm in, the PDQ will state that the card is not supported. If I use Samsung Pay and use the same card, it just declines the transaction. Obviously this really only applies to Amex usage as not everywhere takes it. It's just a bit strange how SP doesn't relay the card being used to the PDQ the same way AP does I found.
I also found that AP, whilst it has a set default card for all contactless payments unless you load the app and "open" another card up, it will remember the last card you had "open" and use that unless you click back to go back to the card selection screen.
So if I was paying by debit card which is not my default card, and I just click the home button to go to the homescreen, AP is still in the background with the debit card open. So when my phone goes to sleep and I'm in another store, I wake the screen up to pay, it uses the debit card instead of the default card.
Anyone else noticed these quirks?