Quite a few features in this one. There's more in the link, but i listed the key ones here...
Library UI Updates
‘This PS4’ and Name/Avatar tabTwo new tabs are being added to Library to make it easier for you to see which apps you’ve installed and purchased. The ‘This PS4’ tab lists all the applications that are installed on the PS4 system, and the tab with your name/avatar lists all the apps that you purchased with your PSN ID. This feature also makes it easy to search and find games you’ve already purchased but have not yet installed.
PS Plus tabThis update also adds a new PS Plus tab to the Library, which clarifies what games you own from PS Plus’ Monthly Free Games. If your PS Plus membership is expired, a PS Plus icon with a lock will appear next to your game so you’ll know you cannot play the game until you’ve re-subscribed.
Hide appsWe’re adding a function that will allow you to hide certain applications under the ‘Purchased’ tab in the Library. In ‘Options,’ you can hide content including betas, trials or demos of games that you probably won’t be going back to.
Notifications UpdateThis update will give you the ability to delete old notifications for better organization and management. Just go to Notifications and press the ‘triangle’ or ‘Options’ button to open up a menu that will allow you to select a single or multiple notifications you’d like to delete.
Import Custom Wallpapers via USBLove customizing your PS4 Home Screen? Well, this new update will give you even more options. You can import your own images to PS4 from a USB stick and set it as your wallpaper. You can also zoom and crop your images so they look perfect on your dashboard. Just go to Settings > Themes > Select Theme > Custom > Select Image > USB Storage Device.
https://blog.us.playstation.com/2018/02/06/new-features-coming-to-ps4-in-system-software-5-50/