Currently I'm running the following:
1. Amazon Echo
2. Harmony Hub (with activities set for WATCH TV, WATCH MOVIE, CHROMECAST)
3. Samsung Smartthings (various light bulbs, motion sensors, leak detectors and wall outlets)
I have the all devices synced\connected to each other.
On the ECHO side I have a GROUP set-up in SETTINGS > CONNECTED HOMES > GROUPS named LIVINGROOM
In my LIVING ROOM GROUP I have the following WATCH TV and READING LIGHT.
If I say "ALEXA, LIVINGROOM ON" it will turn on (with correct inputs\outputs) my TV, HOME ENTERTAINMENT SYSTEM and CABLE BOX and the reading light as well, If I say "ALEXA, LIVING ROOM OFF" it will turn all devices off I also
It's pretty much wide open from what my new to this self can see as far as what you could set up as ACTIVITIES and then sync across to control by voice. Will take some hobby play time though