Do I need a chime of some sort?

Hello folks, I have recently fitted a Ring 2nd generation Doorbell and have hardwired it and everything seems to be working fine. My question revolves around knowing when someone is at the door when my iPhone is not close to me. Do I need to fit some sort of 'chime/ringer' to the doorbell and if so do I need to connect such a device to the transformer that now drives the Ring Doorbell or can it be connected by either wi-fi/Bluetooth? Many thanks.