Colour Clock

Tell the time with colours that change as they rotate round the clock face.
Blobs at the end of the hour, minute, and second regions change colours over
time (red = 12, yellow = 3, green = 6, blue = 9).

This might help younger children to tell the time without having to know what
numbers mean (e.g. it's yellow and orange).

A sine-wave second "tick" has also been implemented, as well as fixing the
minute hand to integer positions. This makes the clock a bit more interesting,
because each hand tells the time in a different way.

Other apps by this developer: https://f-droid.org/packages/org.gringene.concentricclock

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