Why am I only given the option to connect to Roku over my network? I am able to watch Roku on my iPhone.
The Roku app will only connect to a Roku device on a private network. Virtually all public networks have filters that block connected devices from seeing other connected devices. This is a security feature, and one you would never want to disable (even if you could). Many public networks also use an IP address range that is not considered "private" and even if that security feature was turned off the Roku app still wouldn't see your Roku.
There's only one reliable way to access your Roku from an iPad or phone when traveling, and that would be to set up your own private network that can then access the hotel network for Internet access. I did this when I was staying in a hotel for a long term job detail. Mine used a Windows PC to connect to the hotel's WiFi, and then share that Internet connection using the Ethernet port on the computer. I connected a router set to Wireless Access Point mode to the PC, and the router provided both wired and WiFi connections for my various devices. And yes I could access my Roku through my phone doing this. It's a bit complicated to set up, and might be beyond the expertise of many travelers.
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