Shaoduo Xie has released Audio Lab, a new modular synth app for the iPad. Version 1.0 is available now for $0.99.
Audio Lab provides a flexible platform for experiencing the fun of the audio world. It can help you experiment with various audio modules (generator, filter, envelope, etc.) and connect them to each other without restriction.
Audio Lab is more than a synthesizer, it is a living environment. With a few taps of adding and managing modules, you can get a unique audio instrument. Audio Lab provides you a virtual keyboard with 3 octaves, which is enough for testing the sound you make and have fun in playing notes.
More types of modules and features will come with future development.