The Pricing of Software Products is a very sensitive process as development and resource costs can change rapidly.
Just recently Google hiked their prices for the Google Maps API and as a result threatens to ruin small businesses which depend on it and has been and even greater expenditure for other transport and location dependent services which utilise its services.
There are also costs associated with securing the hosting server on which the application is developed as well as its communication protocols, depending on the type of application it may require more security or even require certifications.
Prices can also change vastly depending on the scale of the application - the more users the application serves, the more it will cost to maintain and serve those users.
Depending on the complexity of the application, it may take more time, resulting in more resources being assigned to the project thus increasing the cost.
Depending on the scale of the application, more developers may be contracted to develop it.
Applications usually have set timelines for development, the shorter the timeline the higher the cost.
During the development of the application, new ideas and features may be added to the mix, these features may attract additional costs to implement if they will take much resources to implement or require a change in architecture.