They can barely make a Mac version that doesn't require serious messing around with the application files every update; the developer of the middleware tool (Fungus) is astonished the PC version even
loads, and the zips expand out to about 11GB which would kill any Android device.
So, yes, they did intend to produce an APK version, but when the original SU Rebuilt was abandoned it died with it.
As
OhWee states above, there is a community effort (headed by
xMendoza and himself) to build an unofficial version in Ren'Py and hand it to Gunsmoke Games. For free!* That's how badly developed this application is and how poor at software development the official 'team' are - people are prepared to give their own time to build them one that works, just so we can get updates on time! (and yes, Android versions).
*I'm oversimplifying here.