Somebody else commented this: https://www.gemalto.com/financial/cards/payments/dynamic-code-verification https://www.gemalto.com/financial/cards/payments/dynam

Somebody else commented this: https://www.gemalto.com/financial/cards/payments/dynamic-code-verification https://www.gemalto.com/financial/cards/payments/dynamic-cod... I suppose if you can fit it inside of a credit card it would fit a case, and it would be really cool.