Here is an interesting approach to the technological hurdles of mobile banking. Called Cashnxt, this venture in Kerala, uses high-pitched sounds via mobile phones to encrypt and decrypt the secure data needed to perform a financial transaction. An article on ReadWriteWeb, explains it as such:
As a customer, if you and a vendor are a member of the Cashnxt network, you can conduct transactions using your mobile phones. The merchant dials CashNxt’s IVR number, enters their PIN and transaction amount, and then hears a high pitch sound on their mobile phone. The customer does the same – calls the IVR number, enters their PIN and hears a high pitch sound. The two phones are then brought together, held close enough for CashNxt to encrypt and decrypt the sounds.
Go after the jump to see a youtube video of the process: