This will bring something new. It may seem like a little detail but it's definitely not. Your device will just look different from others. Try it out!
The author mohammad_adib has made a really good app. Besides this, you can set the shape size (radius of the shape), staus bar overlap or enabling on lockscreen.
Expect the round corners, the author has made an extension, which brings new opportunities. This app offers 10 new corner-styles and BlackList for blocked apps.
This extension costs 1.9$ and you can get it HERE
The main app, roundr is completely free.