Free Newsletter Get the hottest Fintech Singapore News once a month in your InboxTap a multi-currency card in Tokyo, and the payment looks no different from any other card transaction. LuLu Exchange encountered an operating challenge when it set out to build a multi-currency card programme in the UAE. Why Several Wallets Change the ArchitectureOne the one hand, a conventional card usually checks one primary balance before approving a transaction. Adding a currency can require changes across the wider card programme, not just the wallet itself. One authorisation can therefore draw from more than one currency balance without asking the customer to move money manually before paying.