We have integrated the Nordic Semiconductor nRF8001 module with the spark core and have provided a simple UART over BLE interface to connect the Spark core to a phone. The BLE can be used to get WiFi credentials and also to return debug information for issues the Spark have when connecting to WiFi.
So this is useful for troubleshooting and is an easier method to set WiFi credentials.
This is now available as a spark.io library (NRF8001-BLE-UART-SPARK-IO) so you can play with it.
You can use the Adafruit BLE module or the Rebearlab shield to or the Jaycon nRF8001 breakout board to connect to the Spark core.
More documentation is on our github repo for the NRF8001-BLE-UART-SPARK-IO library.
You can use the nRF UART apps in the Apple app store and Google play to communicate over BLE to the Spark Core.
Please remember that in today’s spark configuration, the Core checks WiFi before it runs the BLE module, so getting WiFi credentials over BLE would require that the BLE library is run before checking the WiFi.