The app works as always, with low power usage.
How many apps are active / background in the navigation?
Check the battery statistics to see which app really uses it.
Is the battery in good condition or the charger sufficient?
(old batteries run out quickly)
See the changelog and the new features here.
Which of these do you use?
Otherwise post all app settings, some may use more cpu / gpu,
like animations, kalman, etc.
Could reset app settings and test with the defaults.
And select Google location service in app settings.
Have you tried another charger?