[Elecraft] Using KX3 with Android device...

[Mark, KE6BB]

I have used KX3 Companion on my my Android phone (Samsung Galaxy S5) using a USB OTG cable and the Elecraft KXUSB cable for rig control.  If you want a waterfall, you will need to add the appropriate audio cable.
No special Android requirements.  I don't use it much though.  Far simpler to control the radio from its own front panel IMHO.
Markars: KE6BB