In an ideal world, every audible alarm would include a visual indication that something was wrong, so that the hearing impaired would immediately be notified too. Until that happens, a $1.29 app called Deafalarm could serve as a viable alternative -- keeping an ear out for alarms and alerting the user through text and vibrating alerts.
Like Shazam's song-recognising app that can now be set to listen 24/7, Deafalarm runs in the background on your iPhone, constantly listening for repetitive sounds that indicate an audible alarm is going off. When one is recognised, the app provides a vibrating alert in addition to an on-screen notification that something might be amiss.
The app will also vibrate if it's been shut down accidentally, or if the iPhone's battery has dropped so low that it will shut down, so a user knows that Deafalarm is no longer listening. And while there's the chance the app might be fooled by non-alarms, that's a minor inconvenience for the times when it's right. [iTunes App Store via Medgadget]