Look...you asked "A 190-4; A 131; A 118; A 138 + sequencer app on my iPad. I’m trying to do something, but it doesn’t work... Probably I need more modules (I know that), but I would like know if it’s possible to get something with my current set."
And you got an answer. Sorry if you don't like the answer, but at least I'm going to step up and tell you the true answer to that question. I'm not going to tell you that you're off to an awesome start, because that would be a total lie, at least as far as your module choices are concerned. I'm also not lying when I note that your A-190-4 has nothing to talk to. You have a MIDI interface, an exponential VCA, a noise/random generator (as the only thing that makes sound here) and some sort of mixer (which I can't discern because that "138" needs a letter after it, and you didn't provide one). None of that can do much with CVs from the A-190-4, and about the only control you would have with that would be to use a gate signal (note on/note off messages) to open and close the VCA. And that isn't a synthesizer. It isn't even close to being a synthesizer. And you wanted to know if it's possible to get something with that module complement, and now you're all butthurt because someone stepped up and told you the plain truth about what you spent money on. Boo. Hoo. Would you rather I tell you that you're well on your way to being the next Deadmaus? You'll have a long wait for that to happen. Like, forever, if you keep following this sort of tangent of cobbling together random modules, asking what you can do with them, then getting all torquey when someone steps up with some actual facts.
Sure, you can make sounds with the iPad. That won't help with the modules you've listed, though, and your selections belie that you haven't "studied" much of anything about this. And you should note that I offered you some very good advice in that you need to get a much clearer understanding of analog synthesis architecture with some hands-on work with a real synth. Not some virtual thing on a tablet, but the actual device...which is a very different sort of creature than poking around at virtual controls that control emulations of circuits which, in the real world, don't necessarily behave like some goof-proof modelled thing in dataland. Again: go and get a patchable synthesizer, like a Moog Mother32 or an Arturia MiniBrute2 or even a Behringer Neutron and you will not only see exactly what I'm getting at here, you might wind up learning why and how you made some mistakes with those module choices and your expectations of their usability.