The problem I have with nav apps is that they use databases which are out of date by the time they're issued. Same with my nuvi with lifetime maps... which I typically update as soon as the new mapset comes out. And yet there are places I go that have had road changes over a year old that still don't show on the latest mapsets.
That's one thing I like about Waze. I have yet to stump it on my normal travel paths. Otoh, when I ask it to search for something specific in my local area, it doesn't do a very good job of finding what I'm looking for unless I plug in a physical address. And Google even owns Waze.
In contrast, Google Voice Search does a very good job for me on local searches. And it gives me the option of which nav program I want to use to nav to the searched item.