The ability to interact with your android device has been available for some time.
In earlier versions of Android you needed to click on the microphone icon to activate voice commands.
However you can also activate voice commands by saying “OK Google”.
Here is an old Google video showing how it works.
Note: The activation screen has changed since this video was made:
Activating Voice Commands for All screens
You don’t need to be in the the Google now App or any other App to activate voice commands.
You can turn on voice activation for any screen including the lock screen.
Open the Google App and press the main menu iconThen click on settings. Press Voice and then OK Google detection. Enable the from any screen option and follow the instructions.
If you get the message Could not retrieve settings. Then follow the instructions here.
What Can you Do with Voice Commands
You can use Google voice commands to
- Set alarms and reminders
- send email
- send text messages
- make phone calls
- check the weather
- search google
- get directions
- Do Maths
- Play music
Useful articles and videos:
Common Questions and Answers
Q- Can I use OK google to control my lights.
A- Yes -See this article
Q- Can I use OK Google Off line
A- Yes but very limited as it relies on Google Search. You can use it to control your phone or tablet e.g turn bluetooth on or off etc.
Q- I don’t have Google now but Google Assistant what happened?
A- You may have automatically been upgraded to the new Google assistant. See Google Assistant Notes.
Q- Does Google store my voice commands?
A- Yes they are stored on your Google account and can be deleted/edit by going here in web browser or going to Settings>accounts & privacy and MyActivity in the Google App.
This techrepublic article has more details