All of it is calculated on your own device. If you share your location, it is used here and kept in this browser — it is not sent anywhere.
Calculated times can differ by a minute or two from your mosque's timetable. Where they differ, follow your mosque.
On a phone, the dial can turn with you so the gold marker points the way. On a computer, use the bearing with a map or a compass.
This is the Umm al-Qura calendar, which is calculated in advance. A local moon sighting can put the start of a month a day earlier or later.
Tap the bead to count. Choose a target and it tells you when you reach it. Your count is kept if you close the page.