Jasuto is an iPhone music app (and a VST Plugin) that can rightly claim to be the first modular synthesizer on the platform. Jasuto lets you build your own patches or synths similar to how you would in Reaktor or SynthEdit, albiet in a much more simplified environment. Modules are represented on screen as circular objects and connecting them is only a matter of placing them near each other. The orientation of the modules relative to each other matters, since placing a module to the left of another may connect to a different input than placing it to the right. How far apart the modules are determines the volume level. If you've ever seen the reacTable, it's very similar to that. Jasuto comes with simple sequencers, oscillators, filters, effects, and the ability to load samples. Jasuto keeps all the modules fairly simplistic - the goal is to make modular synthesis fun and easy. Each module usually offers only a couple tweakable parameters. For that reason Jasuto falls somewhere between a musical instrument toy and a full music program - it's too complicated to be a toy (synthesizer novices won't get it) and it doesn't have enough options to make a song with.