Currently the sunrise/sunset times is obtained using the online API every time the clock app is opened or specifically when the location is changed. It would be better if there was some data caching such that if the location remains the same, then the clock app retrieves the sunrise/sunset times only once per day. So irrespective of the number of times the clock app is opened, it should only get retrieve it from the online API if it has been a day since it was last retrieved.
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Solution to the bug
When sunrise/sunset times are retrieved from the online API, the date and the sunrise/sunset times should be stored into the local database to remember the last time when it was retrieved online. Modify EasterEgg.qml to check the date and if necessary fetch online, otherwise just show the saved sunrise/sunset times.
Difficulty: Medium
Fix committed into lp:ubuntu-clock-app at revision 178, scheduled for release in ubuntu-clock-app, milestone usable-state