How Cairo's times are computed
For Cairo (30.05° N, 31.25° E) Hourora computes the sun's position for each date and solves for each prayer: Fajr 19.5°, Isha 17.5°. Asr uses the standard shadow rule. The times are shown in Eastern European Summer Time, daylight saving included.
The default is the method usually published in Egypt: Egyptian General Authority of Survey. You can choose another method, the Asr rule and the high-latitude rule above; the choice is saved on this device.