(1) I downloaded the Chordana Play APP from Google Play into an inexpensive Motorola G5 phone, and connected it to my Casio LK-S250 with a
Cable Creation Micro USB to Micro USB Cable, (0.56ft to 4ft) Coiled Micro USB OTG Cable from Amazon ($7.99).
Everything works fine.
(2) Important Note: At first I tried an Android Tablet with the following cable set up:
Tablet - usb micro to usb female OTG - usb male to usb micro - keyboard,
"but this did not work."