Apps tend to be discounted sometimes. But how can you find out when the app you want is discounted? For this, I like to use AppShopper.
AppShopper is an app to keep you up to date on App Store updates, freebies, and discounts. Create a wish list, and it will provide push notifications on when the app has been updated, discounted, or the price has increased.
As you can see from this screen shot, most apps do get discounted sometimes. I also like to use the app activity screen to see how frequently an app gets discounted or updated.
I'm always on the look out for a new and interesting apps. Please let me know if you have any recommendations!