I am happy that this older application have gotten new life and seems to be developed further. My sadness stems from the fact that it had a much cooler name before making it a true underground app as it was not so easy to find before. Yes you had to scrape the bottom of Playstore search engine to find it and it was not clear that it was a music application at all.
It just had the simple name of SATAN and as logo a "hand drawn" upside down cross.
I downloaded it a long time ago under its old guise and there was no tutorials but after some mucking about it got learned but my device was too slow and SunVox got discovered and SATAN got forgotten...
Well it got some update, remember seeing that it got a Vocoder but it seemed like this open source app was going to be slowly languishing and finally disappear.
Now there is a reboot since some months and first the name got changed and the Logo so maybe there will be some more users now!
It is a little bit like SunVox in that you can combine sound engines and effects in a modular fashion but it does use the more common piano roll sequencer instead of a tracker interface.
It is not as deep or flexible as SunVox but it does come with some nifty things one being able to play the sound engines on Tenori / Pad window being adjusted to whatever scale you chose. There is also the possibility to make your own envelopes for some parameters in the Sound engines. For sure there is some more things that I am missing but it is for free and can be just what rocks your boat!
There is also a tutorial now and a less confusing interface so it is not so hard to figure out as before. The developer is selling himself short as he is not really giving a full description of his app not even mentioning what sound generators or effects are included.
But like said it is for free and without publicity or strange permissions so it is worth to take a look. I have it installed since some time and the idea being is to investigate a little bit deeper but having so much other apps to work with that I already feel comfortable with it will take some time and would love if anyone that is using it or in the future are using it would write me about your experience or music being made with the app and so it could be published here. - email@example.com
Would also love to speak to the developer but it is hard to find any contact email as there is none on the Playstore and the link to the Website just opens to a fixed screen...
So if you read this please write me.
In the end it is one of the more complete applications that you can find even though it seems slightly buggy but there is nothing this advanced for free...