I love being able to control my Roku smart TV with Alexa. I've been having hit-or-miss success with commands, however. I couldn't find a list of all of the Alexa commands for Roku, so I just started trying everything I could think of. Here's my results:
"Alexa, turn on Roku": Works great!
"Alexa, turn off Roku": Also success!
"Alexa, set volume to #": sets volume to the exact number. "Alexa, lower volume on Roku": lowers the volume by 5 points. "Alexa, mute Roku", :mutes the volume at its current level - Excellent!
"Alexa, switch to cable box/turn on cable box/launch cable box": Alexa responds with "OK" but nothing happens. Sometimes a flag "Switching to cable input" is seen in the upper right-hand corner, but the TV never actually shows what's on the cable box.
"Alexa, launch Netflix on Roku": Doesn't work. Known issue.
"Alexa, launch Boomerang on Roku": Alexa responds with, "Hmm... I can't open it right now."
"Alexa, launch Relaxation on Roku": I have a channel called "Relaxation Music and Sound VIDEO" on Roku. No matter which way I call for this channel, Roku performs a search instead of opening it.
"Alexa, launch the Great Courses": I have my Great Courses account linked to Roku, and it shows up as a channel. I had to set this up on the web. This is different, I think, from the standard Great Courses channel, which asks you to subscribe to it. I do not have that one installed. When I try to launch my Great Courses account channel, the Roku shows a flag at the bottom of the screen telling me that "The Great Courses is not installed" and asking if I want to install it. I'm pretty sure it's not actually seeing what I have installed, but rather looking for specific installations of things.
"Alexa, launch YouTube": Works great. Cannot figure out how to get Alexa to pick a video and launch it, however. Is it supposed to be able to do this?
"Alexa, launch Prime Video on Roku": Opens Prime Video. Haven't investigated this further, because my account isn't set up yet.
"Alexa, launch Weather Nation on Roku": Alexa responds with, "Sorry, I couldn't launch it."
"Alexa, launch Adult Swim on Roku": Switches to the antennae. Tells me what's on, but since I don't have an antennae, but a cable box instead, doesn't actually play anything. I also have the Adult Swim channel installed, and it doesn't open that, either.
"Alexa, launch Google Play on Roku": Opens correctly. Trying to find anything on the Google Play menu with Alexa, causes her to do a general search and return a list of results, instead of opening a movie on the Roku.
"Alexa, (go/go to/launch) Featured Free on Roku": Alexa doesn't switch from the home menu and says, "I'm sorry, I'm not sure how to help you with that."
"Alexa, (go to/show) My Feed on Roku": Same results as trying to move from Home to Featured Free
I have many more channels, but this gives a good representation of the types of things I've been experiencing. In a nutshell, Alexa can't actually navigate the Roku menu at all. She can only directly access channels that are enabled, not necessarily loaded on home, and which are completely unique. Channels such as "The Great Courses" which has three different version (account, channel, Great Courses plus) or channels like Adult Swim, which are available through more than one service, confuse her.
So far, it seems that Alexa can power on/off the TV, open big name channels but navigate their selections or menus (It would be helpful if someone compiled a list of WHICH channels), change the volume and switch inputs. Beyond that, it's still rather limited. However, kudos for a great start. Just being able to direct the TV in the dark is a major benefit.
Incidentally (and unrelated), has anyone figured out how to use the Amazon Echo as a speaker paired to a Roku TV? I can't seem to find information on that anywhere. Thanks!