Skyhook Wireless, provider of the iPhone and iPod touch’s Wi-Fi-based location services, has released a report in which it claims that location-aware apps on BlackBerry’s App World service cost roughly four times as much, on average, as those offered on the App Store or Android Marketplace. The study found that the average price of a location-aware app in BlackBerry App World is $13.60, compared with $3.60 in the App Store and $0.84 in…