I see from previous posts that the nav ui has been improved several times before. But I wanted to drop a couple more suggestions that stood out very quickly to me. Keeping in mind that I use my phone for navigation in the landscape mode.
There is a bar at the bottom that obscures a lot of the map at the bottom. That could be made a lot more transparent or simply removed. Just put the menu button and speed info directly on top of the map. I’d put the menu button on one corner and the speed in the other corner. Move the track button under the menu items and off the main screen completely. It would always be accessible from the menu.