I've written up a quick demo application for using the MappyDot as a standalone device.
The example shows the MappyDot connected to an I2C slave 7 segment display which we are using as a measurement readout badge for MakerFaire Adelaide:
There's a small trick to enabling the bootloader for this as the MappyDot is running in master mode during operation. During boot the MappyDot remains in I2C slave mode until the bootloader times out (1 second). So to load new firmware, you reset the MappyDot and run the firmware loading application in this time-frame (it's the same procedure as firmware recovery if you brick the firmware).
This procedure allows you to load any arbitrary code on the MappyDot. The repository has the demo code used for this example.