CALCONIC_ - Build & add interactive calculators to your website! Choose from more than 50 premade calculators or build your own from scratch. No coding required. Free plan available. Zapier Integration. Publish Anywhere.
Anima App - Design, get feedback, convert to code, publish, iterate.
NI AWR Design Environment - NI AWR Design Environment is a circuit design and simulation solution.
Fluid for Sketch - Sketch plugin to make your responsive designs more efficient
Mapnik - Mapnik is a Free Toolkit for developing mapping applications.
Git Sketch Plugin - Version control for designers