A Bitty Software application - http://www.bittysoftware.com
Liven up that Xmas tree! Hang a BBC micro:bit on it and use the Bitty Xmas Bauble app on your phone or tablet to make it display any one of 6 delightful LED animations and play any one of three Xmas tunes.
Don't worry, we recognised there's a risk of driving everyone crazy with Jingle Bells playing over and over, so you can switch off audio or the LED animations or both, all from the convenience of your smartphone.
Hex files and full source code are available for download from www.bittysoftware.com free of charge so you can either use what we provide or if you're feeling more adventurous, can write your own LED patterns or tunes.
Note that to play tunes, you need to connect some audio hardware to your micro:bit. We recommend the Kitronik MI:power board available from https://www.kitronik.co.uk/5610-mipower-board-for-the-bbc-microbit.html but if you prefer you could just connect a piezo buzzer to pin 0 and GND.