Add this one to the list of smartphone applications that guide people through the often complex maze of large urban subway systems.

Exit Strategy helps riders of New York's subway find the correct exit to minimize the time and distance to one's ultimate destination. This can be critical because taking the wrong exit could put you a long way from where you want to go. Further, it can mean having to cross busy streets and other hazards in the concrete jungle.

In the hands of a skilled user, the Exit Strategy app can even help you choose the exact car in a multicar train that will put you closest to your desired exit.

This could be quite useful to people with cognitive challenges or with lots on their mind, or simply for visitors and newcomers to the Big Apple. Unfortunately, it does not seem to provide information on wheelchair accessibility (elevators, specifically). Maybe the developers will add this information in version 2.

Exit strategy will be available for $1.99 on the iPhone and Android phones, and $2.99 for the Blackberry. It will also be made available for the Amazon Kindle at a still higher, but undetermined price.

Check out the New York Times coverage at: http://cityroom.blogs.nytimes.com/2009/07/07/maps-of-subway-platforms-now-on-your-mobile-phone/?hp