[Zubersoft]

At the moment, I am using an open source library for MIDI that supports devices all the way down to 3.2 (I believe). This device has worked well, but it doesn't have support for things like virtual MIDI ports or MIDI over bluetooth (the same creator made a different library for that). In order to support other kinds of connections like virtual MIDI ports, or to connect to devices that don't use the proper class and subclass (or vendor ID), I'm going to need to use the new MIDI library that Google made available with Android 6.0 and later. I already planned on doing this in order to support devices like the Soundbrenner wearable metronome, but it does mean that only users on newer devices will be able to take advantage of the new features. 

I mention all that because once I add support for Google's newer MIDI library, it should also connect like the MIDI BLE connect app you described above (which almost certainly uses the newer MIDI interface).

Mike