Really? Sounds like you are a possible customer... can I interest you in a handlebar mount for your phone?

https://www.quadlockcase.com.au/products/bike-mount

I have one, but I haven't used it since I got a smart watch (I mostly used it to track my speed). I actually really dislike navigation apps, since they tend to take you on strange routes that maybe are slightly shorter? To be fair, I haven't owned a car in 15 years, so I rarely drive.