Just a week after the new beta build of Android Pie for the Galaxy S9 phones, Samsung started seeding the final build. The company is pushing the package to devices mostly in Europe, but according to sources, the UAE and Turkey are also already receiving the latest OS and UI.
The European countries where Samsung is officially pushing the update are Germany, Switzerland, Italy, and the Netherlands. Some Galaxy S9 and Galaxy S9+ devices started receiving notifications as early as Christmas Eve, but now it should start coming to all owners. The key changes are the One UI upgrade over the Samsung Experience interface, the Autofill API and Digital Wellbeing by Android.
To download the Pie update you have to either tap on the update notification, or if you disabled it, to go to Settings and then Software Update. There’s also the possibility do update via wire with the Samsung Smart Switch. Have you received the final Android Pie update? Let us know in the comments.
I'm in Argentina, got a S9+ bought in Italy and no PIE yet...
Probably that's because it's not being pushed yet. Try checking manually. I am using it for more than a week now.