You've probably seen the TV ads for OK Google, but what is OK Google and how do you use it? We explain everything you need to know about OK Google, including how to access the Google Now voice search from any screen on your phone, even if you live outside the US. Also see: How Siri, Cortana and Google Now are replacing our brains 

Using OK Google with Google Assistant

With the launch of the new Pixel smartphones from Google, the firm has also released the Google Assistant. It’s a new way of interacting with the service in a conversational style.

Google Assistant is ‘built-in’ to the Pixel phones (that run Android 7.1 Nougat) which means it’s pre-installed and can be accessed by long pressing the home button. However, it’s what will load up if you say ‘Ok Google’ instead of Google Now.

You can do all the same things as before and even some new commands including joke telling, games and searching your pictures for a time period or person. The service will be available for Android phones in general in the form of an app some point in the future.

Google Assistant on Pixel XL

What is OK Google? 

"OK Google" is the voice command used to activate Google Now voice search on your Android smartphone, as well as other Google devices such as its Google Glass smartglasses (check out our awesome video of Google Glass). 

Google Now can be accessed by opening your phone's Google Search app or Google Search widget and either tapping the microphone icon or saying "OK Google". On some handsets (notably the Moto X) it even works when the phone is in sleep mode, while other phones have the search bar on the home screen, so you can say OK Google right there. If you're having trouble getting it working, see our OK Google troubleshooter.

Alternatively, you can set up your Android smartphone to recognise the "OK Google" command no matter in what app or screen you're currently browsing. This latter feature is technically available to users in the US, but don't let that stop you... Also see: Android Advisor.

What is OK Google? How to use OK Google from any screen of your phone in the UK

What can you ask OK Google?

You can ask Google Now pretty much anything you like, just as you normally would with Google Search. However, you can also use the "OK Google" command to set alarms, make calls and texts, schedule meetings and more on your Android device.

•    Open (eg. pcadvisor.co.uk, BBC iPlayer app)
•    Take a picture/photo
•    Record a video
•    Set an alarm for…
•    Set a timer for…
•    Remind me to… (includes times and locations)
•    Make a note
•    Create a calendar event
•    What is my schedule for tomorrow?
•    Where's my package?
•    Find…
•    Call…
•    Text…
•    Send email to…
•    Post to…
•    Where is the nearest…?
•    Navigate to…
•    Directions to…
•    Where is…?
•    Show me my flight info
•    Where's my hotel?
•    What are some attractions around here?
•    How do you say [hello] in [Japanese]?
•    What is [100 pounts] in [dollars]?
•    What's the flight status of…?
•    Play some music (opens "I'm feeling lucky" radio station in Google Play Music)
•    Next Song / Pause Song
•    Play/watch/read… (content must be in Google Play library)
•    What's this song?
•    Do a barrel roll
•    Beam me up Scotty (audio response)
•    Make me a sandwich (audio response)
•    Up, up, down, down, left, right, left, right (audio response)
•    Who are you? (audio response)
•    When am I? (audio response)

For example, you might tell it to "Call Jonathan Robson", "Show me walking directions to get home", "Text Margo to say I'll be home at half past seven", "Remember to book flights tomorrow", "Schedule a meeting tomorrow with Matt", "Open Calendar app", "Listen to Diamonds by Rihanna" or whatever you like.

What is OK Google? How to use OK Google from any screen of your phone in the UK

One of the more recent additions is seven degrees of Bacon, so you can ask, for example "What is Daniel Radcliffe's Bacon number?".

How to use OK Google

You can also use OK Google in the kitchen as a kind of sous chef. For example, as above, you could ask it "What's Kohlrabi?" when faced with an unknown ingredient in a recipe.

Speaking is usually quicker than typing, and using OK Google you can say "how far is it to..." and get a quick answer with a route in Google Maps from your current destination. You can be specific about the type of directions by qualifying the question: "Give me driving directions to Amsterdam".

How to use OK Google

If you're not in a position to use voice search, you can also type in your request. 

How to use OK Google from any screen, even outside the US 

You can bring up Google's voice assistant from any screen on your Android smartphone, even when your device is charging. The screen simply needs to be switched on. 

Technically this capability is available only to users in the US, but here we'll show you how to use OK Google from any screen in the UK or elsewhere. 

Note that your device must be running Android 4.3 KitKat or later, and that you must have the latest version of the Google Search app installed. Audio history (Settings, Language & input, Voice Search, Audio history) must also be turned on. 

Go to your phone's Settings menu, then tap Language & input. Choose Voice Search, then tap 'Default - English (UK)' to change it to 'English…', then select 'English (US)'. 

Still in the Settings, Language & input, Voice Search menu, tap '"OK Google" Detection'. Enable the option 'From any screen'. 

What is OK Google? How to use OK Google from any screen of your phone in the UK

Google will ask you to agree to a recording of your voice being stored on its servers each time you use the "OK Google" command. It says this is to help it recognise your voice and improve speech recognition. Tap I Agree. 

Now you need to teach Google Now to recognise your voice. Hold your phone at arm's length and say "OK Google" three times to teach it your voice. 

What is OK Google? How to use OK Google from any screen of your phone in the UK

That's it. You can now call up Google Now using the "OK Google" command from any screen on your phone.

Also see how to fix problems with the "OK Google" voice command on Android smartphones.

Read next: Best new phones coming in 2017

Follow Marie Brewis on Twitter.