If you haven’t heard of Now on Tap before, that may be because Google hasn’t done a great job of marketing the feature. It’s only available on Android 6.0 Marshmallow devices and above, and is triggered when you press and hold the home button in any app, or on any screen. When you press and hold it for the first time, it will say that you have “discovered” Now on Tap — it’s almost as though Google doesn’t want you to use the feature.
Now on Tap analyzes the information on the screen you trigger it on. For example, assuming a friend messages you plans to meet at a restaurant at a specific time, if you press and hold the home button on that conversation, Now on Tap will offer to create a calendar event with the data provided. You can fill in the rest if it doesn’t have enough.
It’s also essentially a hands-free way to run a Google search based on what you’re looking at — if you come across a mention of Sundar Pichai in a news reader app, triggering Now on Tap will offer up more information about the Google CEO, with links to his Twitter, other social networks, and websites. 
And while it was previously difficult to analyze specific text on a page as Now on Tap would just read everything, Google is now letting you trigger Now on Tap after you highlight a specific word so that it offers more precise information. This is reminiscent of Google Goggles, where you could highlight text after taking a picture to run searches — surprisingly, Google hasn’t killed off that app yet, even though it hasn’t been updated since 2014.
“For example, if you’re reading a news article you can select a specific word, like crustacean, and get a definition and links to relevant apps,” writes Aneto Okonkwo, product manager at Google Search.
If you’re looking at images, you can now use Now on Tap to run image searches for more information. Google offers up the example of looking at a sequoia tree, and tapping and holding Now on Tap. This will bring up information about the Sequoia National Park, and General Sherman — the man that particular sequoia was named after.
Arguably the coolest new feature is the ability to run a Now on Tap search in the camera app in real time. Say you’re looking at the George Washington Bridge and you want more information on it — if you point your smartphone’s camera at the bridge and trigger Now on Tap, it will bring up results in the camera app.
“This works for more than just famous structures like the Bay Bridge, you can even point your camera at a movie poster or magazine and get additional info about what you’re looking at,” Okonkwo says.
No updates are necessary to get these feature, thanks to it just being a server-side switch. They’re available now, but word definitions are only available in English at the moment. Google says it will be rolling out to other languages in the coming weeks.
