Maybe Bitwig is worth a look? I’ve got it set on my Mac but there is a Linux version as well. In terms of apps I know Cubasis and Koala exist on Android. Cubasis comes with a set of great built in synths and some extras you can buy, if you need them.
I’m thinking of selling the SeqTrak, not because I don’t like it, it’s brilliant but I’m not sure it fits my workflow and I’ve barely touched it 😏
I just spent money on drum stuff, so not buying anything else for now. I'll push on with my online lessons as I've paid for them.
No worries.