Since the game is so different than the average iPhone game, I wanted to make sure there were as few barriers to entry as possible. The game is free to play and well within the OTA filesize limits. In order for fans to support my effort and further development, the game includes advertisements and several optional in-app purchases.
One IAP simply allows players the ability to get rid of the ads for a more premium experience. The other two provide players with additional content. The Deep Space Network Mission Pack adds another twenty levels to the game. These missions are almost all of the multi-target variety (scan two or more bodies to complete the mission), and they really up the challenge level and strategic thinking quota.
Here's a quick clip of one such level:
In addition to new configurations of planets and moons, the additional missions also include a few exclusives not found in the main game, like Titan, Eris, and the upcoming Comet ISON.
Another in-app purchase is the Probe Variety Pack. This unlocks an additional five probe "skins," allowing players the option of launching Cassini-Huygens, Juno, or another probe in lieu of Voyager.
Even though the game was just released, I'm already working on an update to further improve the user experience. Players will be able to switch between their probes on the main menu without visiting another sub-menu. The level set select menu now includes a progress bar, for a glance-able summary of just how much the player has accomplished.
And finally, as an incentive for users to rate the game, I'll be including a free bonus probe, Mariner 2.
It's still too early to tell if a "serious" "casual" game about space exploration is going to resonate on the App Store, but I'm definitely hoping there is room out there for something different.