Google Play · Android

Matrix Clock

Precision timing anywhere. Crossing time zones should not mean recalculating when to wake up — set the alarm in the time zone you are actually thinking in.

What it does

Built for aircrew and frequent flyers, and useful to anyone whose day spans zones.

Alarms in UTC, GMT or local

Set an alarm directly in the time your roster or itinerary is written in. No mental arithmetic, and no need to touch your device’s own clock.

Accurate to the second

Synced to internet time servers rather than trusting the handset, and it tells you plainly when it is running on the device clock instead.

In-flight crew rest

Plans rest windows across a sector and refuses to draw one that will not fit, rather than quietly producing a window that is wrong.

Flight and block time

Works out block, airborne, day and night time from the times you already write down, with the day–night split calculated from the sun.

The facts

PriceUS$2 on Google Play
Current version2.11
PlatformAndroid, from Google Play
FormerlySky Alarm, then Sky Matrix Clock — same app throughout.
DataEverything stays on your device.

Already installed Matrix Clock from this site? Keep it — it goes on working. The Google Play copy is signed by Google Play rather than by the key the website build used, so Android will not install it over a sideloaded copy: you would have to uninstall the one you have first, and uninstalling erases its alarms, rest plans and settings.