One of the many new features in Android O is a revamped UI tuner with control over the navigation bar. If the layout of the buttons isn't right, you can change it. Want more buttons? Oh, it's got that too. In fact, you can add some useful things there, like left and right cursor buttons. Here's how.

Step one is to turn on the UI tuner, which is the same as always. Long-press the settings gear at the top of the quick settings. Next, go to the system menu and find UI tuner. The Navigation bar section should be right there. We're looking for the extra left and right buttons. You can set each one to Clipboard, keyboard switch, or keycode. That last one is the most powerful, so choose it. Use this list from the Android dev site to find the right codes, and add them.

Left is 21 and right is 22. Add those to the left and right button codes and then pick an icon. For these, we have standard arrows available. And that's it! Now you can move through text by tapping these nav buttons.

That's not all, though. You could also have the clipboard on one button, and add 279 (paste) to the other. Here are some other cool codes you can use:

  • Calendar (208)
  • Play/Pause (85)
  • Dialer (5)

These codes didn't seem to work for us:

  • Camera (27, seems buggy)
  • Calculator (210, seems buggy)

Once again, you can find more keycodes to use here.

There are a ton of things you could do with this. Developers might even muck around in here and come up with some cool apps. They'll probably break in future versions of Android, but that doesn't mean you can't enjoy it while it lasts.