Vital is described as 'spectral warping wavetable synthesizer with drag'n'drop modulation workflow and animated preview of the synth's inner workings where needed. Comes with many modulation sources (including audio-rate), MPE support and FX chain' and is an app in the Audio & Music category. There are five alternatives to Vital for Windows, Mac, Linux and BSD. The best alternative is Surge Synthesizer, which is both free and Open Source. Other great apps like Vital are Helm (Free, Open Source), ZynAddSubFX (Freemium, Open Source), Serum (Paid) and GiMeSpace TouchSpace Synth (Paid).
ZynAddSubFX is a fully featured open source software synthesizer capable of making a countless number of instruments, from some common heard from expensive hardware to interesting sounds that you'll boost to an amazing universe of sounds.
This program was created to make playing music on a computer more intuitive and affordable for anyone who wants to make music. It offers the most natural way to make music by simply using your touch screen or your hand in front of the web cam.