A modern aid for an ancient tradition, Athan Basic helps Muslims perform daily prayers anywhere in the world. On first start-up, you choose your location from a pull-down list of cities and towns. From there, Athan Basic runs in the background, automatically issuing the call to prayer at the appropriate times each day.
You can choose an Athan from Makkah, Madina, or Al-Aqsa (the for-pay version includes several more); the program supports the Standard and Hanafi juristic methods and a variety of ways to calculate sunrise and sunset. The neatly organized application window displays your latitude and longitude and a simple compass for orienting yourself toward Mecca.
If you're often far from your computer, you can print out prayer times for a month. Happily, the program doesn't take much system memory while running in the background. Straightforward and helpful, Athan Basic is a great download for observant Muslims.