Android O Developer Preview 2 brings a revamped Pixel launcher, but it is available only on Google Pixel smartphone. If you are impressed with the new Android O Pixel launcher, a ported version is now available as an APK file, which you can install on any Android phone runs Android Marshmallow and up. If your phone is running on Android Nougat, you will also get the new app shortcut feature.
Thanks to the XDA developer linuxct for making a fully functional backport of the Google Pixel launcher for older Android versions. If you are still on the Android Marshmallow or Nougat, but want to experience the Android O launcher on it, then install the APK of this launcher and make it as your default launcher. The launcher works flawlessly and brings a shiny look to your phone.
Before installing the Android O launcher on your phone, you should first remove any old Pixel launcher installed on your phone. After removing the launcher, just install the new Android O Pixel Launcher APK and make it default home launcher.
Also, note that you should install Google Wallpaper app, if you want to change wallpaper with in the launcher. Install Google Wallpaper (Play store link) and then proceed with installing Android O Pixel Launcher APK.
1. Download ported Android O Pixel launcher APK file from source here and save it on your phone.
2. Enable ‘Unknown Sources’ options in Settings menu, under ‘Security’ options.
3. Tap on the Android O Pixel launcher apk to install it.
4. After installing the Android O launcher, go to settings > home app, choose Pixel launcher and then reboot your phone. (Source – XDA)