[MOD EDIT - thread split from Curve Metal on TFL readers]
On TfL, why not use Apple Pay or Google pay instead of a physical card? It’s so much easier. For example, I just put my wrist close to the yellow card reader and my Apple Watch works through my sleaves. After TfL started supporting Express Travel (known as Express Transit in US English) on 1st December 2019, I don’t even have to authenticate the transaction.