Why did map apps downgrade after upgrading iOS 6?

Question

I expect upgrading OS means every apps got improvement. But why did my google map downgrade into apple map? Does anyone know the reason?
http://reviews.cnet.com/software/google-maps/4505-3513_7-35454676.html
Google Maps review
The good: Map layers, turn-by-turn navigation, Street View, and offline access make Google Maps almost unbeatable.
The bad: No 3D city view.
The bottom line: With its impressive list of features and syncing of data across other devices, Google Maps is a must-have application for anyone running Android.
As far as mobile mapping goes, the newest version of Google Maps for Android offers one of the most robust experiences you can get. More than a simple piece of mapping software, this feature-fest offers turn-by-turn navigation, voice search, indoor mapping (select locations), public transportation information, Street View, and tons of other conveniences. Further, if you use Google Maps on your other devices while signed in to your Google account, your search history, Places, and custom maps sync seamlessly.
(Credit: Screenshot by Jaymar Cabebe/CNET)
When viewing a location, Google Maps lets you activate a variety of add-on layers offering information like traffic, terrain, transit lines, satellite images, and bicycle routes, among others. There's even a Wikipedia layer that plots out entries related to your location, which is great for curious travelers. If you've made any custom maps on your Google account, you can overlay those as well.
If the add-on layers aren't enough, Google Maps lets you zoom into satellite photos to get a close look at buildings and street details. You can even activate street view to get a ground-level look at areas that have coverage. Unfortunately, though, the Google Maps app does not come with 3D flyover images baked in. To get these highly detailed images, you'll have to download it's sister app Google Earth. Hopefully at some point, these two titles merge to offer a more streamlined user experience.
One of the most important aspects of Google Maps for Android is directions. The app lets you easily conduct a search for a destination with text or voice, so you can get directions for driving, public transit, walking, or even biking. You can read your route in list form or hit the arrow icon to activate voice-guided turn-by-turn navigation. While traveling you can even fire up alternate routes if you happen to run into traffic.
Google Maps for Android (pictures)
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But Google Maps is a lot more than just a database of geographic information. The application offers other baked-in services like Offers for nearby deals, Local search powered by Google Places and Zagat, and Latitude for locating Google contacts on the map (with their permission, of course). These services in aggregate make for a complete mobile experience that is pretty hard to beat.
Google Maps for Android now lets you cache maps for access while offline. This is hugely useful for travelers who frequently find themselves in areas outside of their home mobile networks. The feature lets you pinch and drag to determine the area you want to cache, and it tells you how much memory the saved file will cost you.

Answer 1

Had it happen on my iphone 4 that I use as an ipod now and I did a complete restore and it fixed the problem. I did do the over the air update the first time and this time I did it by connecting to itunes.