What is missing is operating system level support for Bluetooth 5, and that comes with Android 8.o Oreo. (androidauthority.com)
By building the USB stack into Honeycomb, the platform now gets USB host abilities and tablets running Honeycomb now have operating system level - support for managing USB peripherals — including gamepads, joysticks, and storage devices — directly. (pcworld.com)
This is all great news, but there is one catch: Android 3.1 still isn't intended, at the operating system level, for managing external storage devices. (pcworld.com)