The biggest part of the cost would be the hourly rates of developers multiplied by the time necessary to develop and launch an app. The time, in its turn, will depend on the complexity and number of features you’d like to implement, and the technology you wish to use.
Technology like augmented reality takes a lot of time to implement if done from scratch. Security of streamed data can also prolong the development if done by specialists without relevant experience. But with an experienced team, these tasks can be completed faster, with fewer blunders, and, consequently, will cost less.