The free Fing app, available for Android or iOS, will tell you the internal IP addresses of all the devices on your network.
What make and model of TV?
What make and model of phone?
How does Now come into this?
In general, you can pair the Roku app with a Now or Roku device that is already configured, but you need the physical remote to start from scratch, or start again after a device reset.
However, I’m not sure if this is what you are asking about?
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