Acquiring and maintaining map and routing data is extremely resource intensive. Licensing the data is, accordingly, expensive, and updates to the data simply can’t be free for the lifetime of the product.

Moreover, any internet service required to support the application costs real money. If you can’t charge subscription rates, then the only other business model is subsidization of services via advertising. Seeing as advertising dollars come out of the consumer’s pocket (at pennies on the dollar, considering the services rendered), I don’t see a forced move to the advertising business model as a net societal gain.

Heck, if you’re worried about this, charge twice as much.

The subscription for maps is legitimate. Again, there’s no way for the store to handle this at the time of purchase. Of course, the solution is to have users register for subscriptions when they first launch the application.

The background application issue is legitimate. In answer to your question, the reason is because the phone then becomes something which is only usable for one thing at a time.

While I’m not convinced of how useful CitySense is–no offense to the concept, it’s just not my style–take a typical driving example: my users want audible directions. “Turn right onto Main Street in 100 feet,” is a nice warning to receive as you’re driving to your destination. In fact, I probably would want it to interrupt my phone call. Of course, once I get a phone call, I stop getting directions. Or if I check my calendar. Or if I decide to change playlists. Or do anything other than leave my application running on the phone.