This Bluetooth serial module provides a bridge from Bluetooth to UART, and allows you to get a remote, wireless Python prompt (a REPL) over Bluetooth. Note that this module does not pair with iPad or iPhone, but does pair with Android.
This is a HC-05 Bluetooth 2.1 module implementing the Bluetooth Serial Port Profile (SPP). You connect the RX/TX pins on the module to TX/RX pins on the pyboard (as well as power). You can then use the UART object on the pyboard to send and receive characters to a paired Bluetooth device (eg Android phone or PC). You can also redirect the REPL to the UART to have a wireless Python prompt.