You can enable any skill available through the Alexa App or at alexa.amazon.com, however here’s a quick way to understand the difference between 3rd party Alexa skills and ecobee Smart Home skills on your ecobee4.
3rd Party Alexa skills
These are any skills that you enable through the Alexa App or through alexa.amazon.com that do not control your thermostat. Alexa Voice Service has built-in voice commands ready to use, but additional skills need to be enabled before you can use them. They can range from trivia games to daily news.
For a list of built-in Alexa voice commands that you can use with your ecobee4, click here.
ecobee Smart Home skills
The ecobee Smart Home skills allow you to control your ecobee thermostat using Alexa enabled devices such as Amazon Echo, Dot, or Tap. Since ecobee4 comes with built-in Alexa Voice Service, you can also give voice commands to your ecobee4 to control all your ecobee thermostats. You must enable the ecobee skill before you can control your thermostat using your voice.
For a list of ecobee thermostat voice commands, click here.
To learn how to enable the ecobee skill, click here.