I have the Navionics nav app on my phone and it truly is remarkable. In fact, I'm thinking it's far better than my CP and it's a rival for Rose Point Coastal Explorer. However, it doesn't have ActiveCaptain integration and I don't have wireless AIS on my boat, so CE is still my "go to" primary nav application and I use Skipper for ActiveCaptain on iOS.

The auto-routing function is good for "let me do a quick estimate for how far from here to there" and it works very well most of the time, but I wouldn't trust it without checking the route details manually.