Wayward Souls resembles a relatively standard 2D roleplaying game, albeit with one big twist: Each time the game is patched, it goes up in price.
Developed by Rocketcat Games, Wayward Souls can currently be purchased from iTunes at a price of $5. As the game's listing states, each time Rocketcat issues an update for the game, its price will increase by $1. Rocketcat offers no specific word on how many updates it has in mind, or if Wayward Souls has a maximum price, but does note that "several" updates are planned.
As for why Rocketcat would introduce such a unique pricing scheme, the reasons are two-fold. First, it encourages players to buy Wayward Souls early in the game's life - or, at least, it would, assuming players are aware of the developer's planned price increases. Second, it pushes Rocketcat's development team to ensure that each Wayward Souls update is substantial enough to warrant an additional $1 from players.
This early in the game's lifespan, it's unknown if Rocketcat will hold up its end of this implicit agreement, but if nothing else, this should be an interesting experiment in what pricing schemes iOS gamers are willing to tolerate.