[howardbeware]

I saw this on Instructables' FB page this morning and was reminded of some similar open source BLE efforts. Some of the notable ones are:

Tah: BLE central role AND periperal role AND iBeacon; USB HID via male USB and programmable over USB, 12 analog inputs, 7 PWM outputs, 20 digital I/O; https://www.crowdsupply.com/revealing-hour/tah-open-ble-ardu...

BLEduino: BLE peripheral role only; USB HID via micro-USB; 9 analog inputs, 6 PWM outputs, 20 digital I/O; http://bleduino.cc/

Blend: BLE peripheral role only; USB HID via micro-USB; 10 analog inputs, 6 PWM outputs, 17 digital I/O; http://redbearlab.com/blend/

Bean: BLE peripheral role only; no USB; 2 analog inputs, 4 PWM outputs, 8 digital I/O; http://punchthrough.com/bean

As for pricing, they all seemed about the same, $30-$50, but it was hard to tell because some of them included free shipping (e.g. Tah) and some didn't.