They might be for niche audiences, but the world's first audio-only iPhone game, Aurifi (or-if-EYE) was released a few weeks ago and the second one, Papa Sangre, is slated to be released in September.
What's behind this new trend in gaming?
It isn't new technology, which is fairly commonplace in the industry, says Aurifi developer Chris Walker of Punk Pie.
Walker said they mainly used Apple's Logic software and plug-ins to create the game, which contains several mini-games in which players use only audio-cues to complete tasks.
Instead, like many iPhone-app stories, it's mostly the new distribution system that's helping these sorts of apps come to life.
Before the iTunes store, designers had to come up with a concept, convince a developer, and secure a publisher. Nowadays, "if we can find a small amount of funding, we can execute the game," Walker says, which allows for a lot more adventurous developing.
Once they'd decided to create an audio only game, Punk Pie chose the iPhone because it was one of the first phones to support 3D audio, and has better market penetration than other phones.
Walker admits that the game is for niche audiences, but suspects audio-only will become a genre because "to be noticed at all in computer games now, it requires something different."
Aurifi has over 11,000 active users within its first 8 weeks, and is particularly popular among visually impaired users. That's not enough to make Walker the next app-store millionaire, but the app has pulled in thousands of dollars since launching.
And stay tuned for Papa Sangre, an audio-only 3D thriller game, which is launching in the fall.