Audulus 3
“With Audulus, you can build synthesizers, design new sounds, or process audio. All with low latency real-time processing suitable for live performance. Audulus's user interface is clean, simple, and easy to learn, allowing you to focus on sound - now made easier than ever with nearly 100 built-in Eurorack-style modules.”
–from the App Store description
App type: App
App store link: 
Developer: Audulus LLC
Developer AB Forum Handle:
Additional Info
The Audulus Forum is a great resource for help and support and includes many useful modules for downloading.
There is huge collection (over 140 MB) of example patches that you can download from their forum.
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