For UPI, which is created and run by NPCI (an organization comprising a consortium of private and public banks), there is an “official” app called BHIM (Bharat Interface for Money). Anyone who has it doesn’t have to worry if the other person is using Google Pay or WhatsApp Pay or another app. Banks also have their own UPI apps or include the UPI feature in their banking app. All these apps work on the same platform, which is UPI, which in turn is supported by all banks.