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.
Built for aircrew and frequent flyers, and useful to anyone whose day spans zones.
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.
Synced to internet time servers rather than trusting the handset, and it tells you plainly when it is running on the device clock instead.
Plans rest windows across a sector and refuses to draw one that will not fit, rather than quietly producing a window that is wrong.
Works out block, airborne, day and night time from the times you already write down, with the day–night split calculated from the sun.
| Price | US$2 on Google Play |
| Current version | 2.11 |
| Platform | Android, from Google Play |
| Formerly | Sky Alarm, then Sky Matrix Clock — same app throughout. |
| Data | Everything 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.