Safari browser apps
Back when the original iPhone launched in 2007 there was no support for 3rd party apps and everything you wanted to do outside of what Apple provided was through the Safari web browser. Browser apps and optimization for the browser has come a long way and for some people accessing their favorite mapping service via the Safari browser may be perfectly acceptable. I still think for most people that iOS 6 Maps is more capable than these browser solutions, but if you live in an area with poor map data then you can try these out for free too.
Google may no longer have a dedicated iOS application (I understand this is being developed), but their web utility is quite good and even has an icon to add to your home screen that makes it seem like you have a Google Maps application on board. People seem to think Google Maps was awesome before iOS 6, but it was fairly limited and Google is able to provide much of the same functionality right from within the Safari web browser.
You have an upper right drop down arrow that lets you sign in to your Google account and view all the places you have previously saved or starred. You can toggle layers for satellite view, traffic, and bike routes. Directions are supported for vehicles, buses, walking, and cycling. Similar to the iOS 5 navigation experience you do not get voice guided navigation, just a blue dot that moves on the map. There are zoom in and out buttons and pinch and zoom is also supported.
Nokia Maps is powering the new map solution on Windows Phone 8 and iOS users can enjoy Nokia's maps as well via the Safari web browser. Like Google, you can login to your Nokia account and see all your favorites that you have setup through your Nokia account. One interesting aspect of Nokia Maps is that you can save an area of the map for offline usage, which is pretty incredible for a web-based application. Another very cool feature is support for audio directions!
You can view maps on your phone in map, satellite, public transport, and live traffic views. Layers include accidents, construction, congestion, and other traffic incidents. You can setup a route via automobile, walking, or public transit. The area of your turn is zoomed in right on the display and I almost swore I was using a real application and not even in the browser.
The main thing I like about Bing Maps is that it uses nearly the full display of the iPhone 5. It is a very basic application with support for vehicle, transit, and walking directions, traffic status, and road, aerial, and bird's eye views. It is snappy and the directions appear to be accurate. I do like how you can slide the directions up or the map down to optimize the view of the directions.
There is capability to login to your Bing account so you can get previous search results and I found the search part pretty powerful. It is pretty clear to me though that the Bing Maps solution is the weakest of the three web-based methods I tested out.
Summary and conclusion
As you can see, check out, there are plenty of options available for iOS 6 and iPhone 5 owners. I personally use iOS 6 Maps first, but also want to have an offline solution for those times when I do not have an available wireless connection. I am leaning towards CoPilot Live as my favorite dedicated application. Navigon is right up there as well, but is really quite pricey when you get a free solution on the iPhone 5. I am not a big fan of Waze and MotionX GPS Drive even though they have serious fans and am more of a traditional GPS navigation user. Scout is quick, easy, and offers some great additional functions like movie times and reviews.
I thought I would never use a Safari browser app because they would be too limiting and other 3rd party clients are much better. However, they are actually quite good and Nokia Maps is almost as good as a regular app with downloadable sections of maps and audio directions. Google Maps in the browser is also a solid choice, but Bing Maps is a bit too basic for my needs. I can see how a person could easily go for an all free solution of iOS 6 Maps and Nokia Maps on the iPhone 5.
Apple is already working to improve the map data and performance of Maps and I agree with my colleague, Jason Perlow, when he wrote thatand imagine in a couple of months this will be water under the bridge, much like Antennagate and other things that had people up in arms on the iPhone.