This looks like a major bug to me. The navbar should be sticking to the bottom like it does for all other devices but if I emulate the following codepen on a Samsung device (using Chrome’s emulator for Galaxy S4) the nav bar sticks to the top. Unless this is a chrome error I imagine this is a major issue. Has anyone else come across this issue or fixes to it?
You should definitely read the documentation 
On Android devices tab bar is always on the top so Ionic emulates this state
Here’s a solution if you want to see it on the bottom: