From Delta Vee:
Interval Run guides you with vocal feedback through your interval exercise. Select a workout, tap 'Start' and focus on your exercise, not the watch.HIGHLIGHTS:* Spoken feedback to notify the user when to switch from walking to running (or 8 other types)* Tabata, Couch 2 5K, Gateway to 8K and One Hour Runner programs included.* Customizable intervals* The feedback is spoken over your music (just start the music prior to starting Interval Run)NOTICE:If you cannot hear the spoken feedback (as reported in one of the reviews), please check the following:- Start some music before starting Interval Run. Otherwise, locking the phone will disable speech.- If you don't like to listen to music during exercise, please leave the iPhone/iPod unlocked and disable automatic locking from 'Settings/General'.- Check your volume settings. On the iPhone, Interval Run uses the Ringer volume for speech. You can adjust the ringer volume using the physical volume buttons when music is paused. On the iPod you can bring up the volume dialog by double-clicking the home button.