Pixbar modifies your device's navigation bar to have solid buttons. This is meant to resemble a certain device that has an exclusive on these kinds of buttons. Currently, Pixbar is meant for phones with stock Lollipop and above or LG devices also. This works without any root permissions needed, as well!
Please note that this app does NOT add a navigation bar if your phone uses physical buttons. It is simply an add-on to those that already have navigation bars.
Support for Xperia and other devices with slightly different navigation buttons will be available in a future release.
There are currently three different home button styles to choose from in Pixbar. It is also possible to change them to any color that you want.
Here is what the app currently looks like.