Maybank was the first bank to introduce MobileMoney in Singapore. Subsequently, DBS developed this app called PayLah! which is of a similar concept, allowing one to transfer money to another person on the spot so long as you know his/her mobile number. The receiver needs to download the app, and the money will go into this mobile wallet, and money can then be transferred into your DBS/POSB Bank account.
Be amongst the first 500 to download the app and register and get $5 in your mobile wallet. Try it now! More information from DBS website