There is an app called caustic that is great on a tablet. It costs 10$ but is very powerful. I usually use it more to play around or scribble ideas. The dev is very nice and they have a YouTube channel full of tutorials that are very easy to follow. You can play with it for free but you can't save unless you buy it. If your a noob I recommend following the tutorial for each synth. I am familiar with other software but I still found it useful because there are little features that are not obvious! I can't share the channel on mobile but here is one of the videos!
It's usable on a big phone screen but more tricky. I believe if you buy the program you can get a desktop version as well.
<3