Vela Design Group has added location services and a home location option to its world clock for the iPhone and iPod touch. VelaClock also has features of interest to photographers and astronomers: sunrise, sunset, and three kinds of twilight: civil, nautical, astronomical for both dawn and dusk, duration of daylight, moonrise, moonset, moon phase and tilt and more.
Check It Out: VelaClock 1.3 for iPhone Adds Location Services