This app was mentioned in 3 comments, with an average of 2.00 upvotes
i use to use a lolipop theme back on kitkat but ever since the update, it is no longer able to change the navigation button
https://play.google.com/store/apps/details?id=com.candl.xperia.theme.l.free&hl=en
what are some themes you guys use to change just the navigation button?
You can actually modify the nav buttons stock! Download lollipop lite.
I rooted for Xposed framework, and greenify and adaway. I also removed all the stock Sony apps.
Lollipop lite changes the navbar:
https://play.google.com/store/apps/details?id=com.candl.xperia.theme.l.free
https://play.google.com/store/apps/details?id=com.candl.xperia.theme.l.free
Thats what I'm using at the moment, but I think I'll be making a few tweaks to it.