BTClock - Arduino based clock with bluetooth control

Inspired by the LAMetric display, I have build my own LED display with bluetooth control using a 32x8 LED Matrix and a cheap arduino nano board with bluetooth (Bluething).
It also works with other arduino board + additional bluetooth module (e.g. HC05).

For manual operations, the clock can be controlled with a rotary wheel. You can choose between the following functions:
-clock
-timer/countdown
-stopwatch
-alarm
-display custom text (scolling)
-options

To keep track of the t