The last time I tried the app, its instructions were completely wrong. I had it running in parallel with TomTom, and was testing it on a very well known route. No milestone / waypoints, just a single destination set. NN make 10 mistakes in the first 30 miles, telling me to take the wrong road each time. Many times I could see it wanted to take me into a car park, turn around and come out again. Stopped and double-checked destination and settings. Set it going also in parallel on my partner's phone. Set off again and it failed almost immediately. It felt like it was a pre-Alpha release. OK, I could keep it running in parallel, but then it was doing very strange things with the display which became a distraction.
This was Mar last year. https://forum.myrouteapp.com/topic/8980/first-time-navigation-next-on-android-auto-strange-display-rotation
I didn't try it again. If another free trial was offered I'd have given it another go after a few months.
Maybe I should try again.