Now on Tap performs a Google Search or brings up a Google Now card by using the context of the current screen. Just hold down on the home button and a card will

Now on Tap performs a Google Search or brings up a Google Now card by using the context of the current screen. Just hold down on the home button and a card will pop up related to the current screen. If the main screen displays a YouTube video of a famous actor, you'll get more information about that person. To make this work, holding down the home button allows Google to "read" the screen by combing through the Android text fields and view hierarchy, sending Google that text plus a screenshot. This will work not only in Google apps and in the browser but in third-party apps too, as long as they use the standard Android framework bits. Apps can be data providers for the feature, too; for instance, in the famous actor example above, the IMDB app could provide a link into the app to display the actor's filmography. I know, I'm old, but every time some "feature" like this pops up somewhere, I still can't believe that people don't mind using it.