The Android N had many changes and a large part refers to something global, a new multi-mode and improving Doze, but there are also a number of smaller changes that are likely to make the daily use easier operating system.
One of these small changes that appeared in the Android N, may be a new option to switch applications. The main change – this is a new version of the double-tap the button recent applications.
The new version of the OS, double-clicking this button will take you to the last application that was open. In practice, this means that if you are in the app, double tap switches you to the previous application, so you can switch back and forth.
If you are on a desktop, when you double-click will open the last application, as you can see below.
Also, if you click on the button recent application once, you can scroll through the application menu, one by one, and when you stop, the selected application starts automatically.
And, of course, you can use the button to get a new multi-mode. Long press of a button, will take you into a new mode, and if you are in split screen mode, long press returns you to the full-screen option.