RuPay credit cards are seeing a growth in usage after linking with UPI, with its issuance at 30%, up from a mere 5% in 2022-23. The shift towards UPI-based credit cards on third-party apps like Google Pay and PhonePe poses a challenge for banks, raising concerns about customer retention and cross-selling. Fintech startup Fibe, led by Ashish Goyal, foresees a potential share struggle among top UPI apps.