Despite being available for several months, Google Assistant is still officially restricted to only a handful of devices. The supported devices include the Google Pixel and Google Pixel XL, Google Home, the NVIDIA SHIELD TV (2017) and partially through Google Allo.
Unofficially though, Google Assistant has been available to any user willing to edit their build.prop on Android 7.x Nougat (just add ro.opa.eligible_device=true at the end of the file). You can even try out Assistant on Android Marshmallow so long as you do not mind installing an Xposed Module.
Now, popular Google Apps package provider 'Open GApps' has added an option to enable Google Assistant during installation of Open GApps. This should come in handy to any users of custom ROMs who lament having to remember to modify the build.prop after rebooting. Granted, build.prop tweaks are some of the simplest modifications one can do, but having this done for us while still in recovery is pretty convenient.
The option to enable Google Assistant should be live in the next build of OpenGapps (Feb. 3rd and onwards). Users will be prompted to enable the build.prop modification while in the AROMA installation environment. Since Google Assistant has not yet fully replaced Google Now as it is still missing a few of its features, this option will remain opt-in for any users who desire to take advantage of it.
Do you frequently use Google Assistant on an officially unsupported device? How is your experience? Let us know in the comments below!