Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
Roku does not develop apps/channels for their devices. They are all developed by 3rd parties, except for The Roku Channel and Roku Media Player. You have to ask the provider to create a channel for Roku devices.
HBO has a channel ready for Roku devices, but they are still in negotiation with Roku for distribution. There are a number of threads already here about it, so I won't go into detail here.
Dan Ultra (4640), Ultra (4670), Ultra (4800), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.
I've been with Roku almost since the beginning. They always got apps for everyone and now all of a sudden they're running into these issues. I to would hate to leave roku but if they don't get their head out of the sand and get these deals made and locked down with hbomax and tvision, I fear if there's another major stream app launch and they fail to get it, they're gonna see people leaving them for their competitors.