Ilkone makes mobile phones designed for Islamic customers. Features include:

• Date Converter, to automatically convert between Hijri and Gregorian calendars.
• Qibla Direction, to allow the user to know the direction towards Mecca for prayer.
• The Quran complete text, in both Uthmanic Arabic font and English, with search engine.
• Prayer Timer, with 5,000 cities pre-set, to alert the user when it's time to pray; this can be done with a standard alarm, or with the "azan" voice calling to prayer, with Cairo, Mecca, and Medina variants.

Targeting specific customer bases is not a new phenomenon, but it takes some interesting turns in digital devices. Wired featured an article on kosher devices in the November 2004 issue. There are some good notes on ethnographic research for culturally specific design in the compilation Design Research (Brenda Laurel, ed.).

Thanks to Laura Garcia-Barrio for the link