I've been using my drum module as a trigger device (all sounds processed by my PC computer) so I don't need the features presented by DTX502 Touch app.
I'm able to upload MIDI songs from my PC into the module (thanks to MS Windows compatible application).
While I accept Android OS limitations' excuse (i.e. no 2-way communication) I still wonder why YAMAHA hasn't yet developed any solution for (let's say) Microsoft Windows OS users.
And I hope that such marketing policy is not intentional by YAMAHA.
I haven't got money to spent on an iOS based device JUST TO UPDATE MY DRUM MODULE'S FIRMWARE.
So this is really dissaponting