Is there any APNS endpoint by which I can get a list of all the device tokens on which my app is installed?
I know there is a feedback service which gives a status of devices to whom messages are being sent. But I guess that is after the messages are sent.
I need the device tokens in order to send messages to the apns server from this node.js module - argon's node-apn
There is no API that gives you a list of device tokens where your app is installed.
It's your responsibility to maintain such a list in your server. You add tokens to it every time your app registers for APNS on a new device. You remove from it tokens returned by the feedback service.