[deleted] I don't use my phone to pay for anything so this does not concern me, but one thing to consider, is by using your curve card to pay for something you do not get section 75 insurance, even if you use your credit card through the curve app.
https://www.moneysavingexpert.com/banking/what-is-a-curve-card/
However, it can be useful for one-off payments, for example with virtual cards like Revolut's.