Zmanim is an application for the iPhone and iPod Touch that displays times through-out the day that are relevant to Jewish Law (Halacha).
To use, tap the "i" in the lower right corner and enter the longitude and latitude for your location. You can also choose to enable Location Services to determine your location. On the iPhone, this will use the built-in GPS unit. On the iPod Touch, an internet connection will be required. Optionally, choose the language in which the labels will be displayed. The choices are Ivrit (Hebrew), English with Ashkenazi spellings and English with Israeli (Sepharadi) spellings.
The code is licensed under the GPL, version 2, and is copyright Avi Shevin. Code for calculating sunrise and sunset is from Ken Bloom's zmanim application, also released under the GPL.
The manual is available as a PDF here.
Version 2.3.0 supports calculations of sunrise and sunset taking into account elevation. To change your existing Zmanim Sets to use elevation, refer to this document for instructions on how to add new zmanim.