Starting today, the Android app is getting a slightly updated look with more personal recommendations. Rolling out today, the most apparent change is a move to bigger thumbnails on YouTube's home screen. Video thumbnails are now larger and now form a continuous feed, rather than being split into categories.
However, the most interesting change is the new recommendation system, which is build on machine learning. From :
This isn't just a new coat of paint on the same old Home—we've coupled a fresh design with more relevant personalized recommendations that make it easier to discover videos you'll be excited to watch. The new recommendation system is based on deep neural network technology, which means it can find patterns automatically and keep learning and improving as it goes. Every day, we recommend hundreds of millions of different videos on Home, billions of times, in 76 languages.
The updated look and recommendation engine are both rolling out now, so you should be able to check them out sooner rather than later.