As of late January 2016 I have been using an Adafruit Feather as the board powering the chorder I wear. There are some issues with it when reconnecting to an Android device to which it has already been paired. More often than I like, I find myself having to “forget” the Feather on the phone and re-pair rather than simply reconnect. Other than that minor inconvenience it has been working beautifully. The code was reworked for the feather with Charles Chen and is available on GitHub.
So here is the FeatherChorder, a BLE (Bluetooth Low Energy) Chorder using the Adafruit Feather 32u4 Bluefruit LE
The advantage of using this board is that it has both the LiPo charger and the BLE transceiver built in, reducing the board count for the chorder from three to one. All that is required is to attach the keys and on/off switch, plug in the battery, and then program it over a standard micro usb cable.
Here is the link to the github source:
Download the Latest BLE Build
Once you grab a copy of the code you can find all the chords in the ChordMappings.h file. Change them as you see fit. They are the same as the chords I use on the spiffchorder plus one set of changes - I have added a bunch of android specific chords. Media events, Volume control and the like. I will add a chart here in the not too distant future. In the mean time, the ChordMappings.h file has them.