I looked at Localscope (US$1.99) about a year ago, and liked what I saw. Now version 3, released today, has added bi-directional integration with iOS reminders and a feature that allows you to add geotagged reminders for any location you find in the app. Localscope can remind you with an alert if your are near a location. It integrates with Apple Maps and is a great supplement because it has far more search resources, including Google Local search, Facebook, Twitter, Foursquare, Wikipedia, Citysearch and Yelp.
At the same time, when you have your destination picked out, you can send it to Apple Maps, Google Maps (via Mobile Safari), TomTom, Navigon, MotionX, Magellan Roadmate, Waze and others. I think using this app in conjunction with Apple Maps is a pretty complete local search and navigation solution. Of course, if Apple Maps doesn't have good routing to the destination, that can be a problem.
In my tests of the app here in Arizona, I didn't have any issues. I like the alerts as I near a destination, although it is redundant if you are using another navigation app. The local search database is as complete as any similar app, and then some.
The update requires iOS 6 and supports the iPhone 5.
Localscope packs a lot of information into one little app, and I highly recommend it. Even when Apple Maps gets its promised improvement, Localscope will still be an excellent sidekick for it.