There's already a programming app out with support for Bluetooth LE (techBASIC), and this seems like it could be a good feature for Pythonista.
Here's a site that describes communicating with a Bluetooth sensor on the iPad: http://www.byteworks.us/Byte_Works/Blog/Entries/2012/10/31_Controlling_the_TI_SensorTag_with_techBASIC.html