PayNow is an electronic fund transfer service that allows you to transfer SGD funds¹ instantly to a payee, using the payee's designated mobile number or NRIC/FIN or UEN number instead of his/her bank account number.
A payee can receive funds via PayNow as long as he/she has a Singapore bank account with one of the PayNow participating banks², and has registered his mobile number, UEN or NRIC/FIN as a PayNow Proxy with the participating bank.
¹ You can transfer SGD funds via PayNow up to your maximum daily local interbank transfer limit. You can check and amend this limit via digibank. Daily transfer limit is capped at SGD200k.
² PayNow is only available for participating banks in Singapore. See question 4 for the list of participating banks.