One of the more useful tricks in Windows 10 for phones is the ability to expand notifications in the Action Center.
When you get a list of emails or alerts, only a snippet is previewed, often cutting off much-needed information. Indeed, on Windows Phone 8.1, you often cannot see the whole Toast notification in the Action Center, making it a bit cumbersome.
Now, in Windows 10 you will have a little down arrow that can be tapped. When you initiate the arrow, the full snippet expands, revealing the entire notification. Even better, the OS dims the other notifications bringing the current one to the forefront.
You can even expand Toast notifications when they come in as they too have a the same down/up arrow.
This feature is but one of the many little changes in Windows 10, and we are happy to see it!