The biggest problem of Android is the updates, which are quite slow, or not even a thing. You won't get the Pie update soon unless you are using a Pixel phone, or an Essential PH-1. Thanks to the developer Trey Dev, you can get a glimpse of Android 9 on your device right now. He developed an app called Power Shade, which mimics the Quick settings and Notification shade UI and runs on pre-9.0 devices going back to 5.0.
Install Power Shade
The first thing you have to do is installing the Power Shade app....