web and mobile app prototyping

App Prototyping Tools For Designers

[…] a suite of plugins to let you design with real data in mind. Manage them via the new Craft Manager for incredibly easy updating.

Principle makes it easy to create animated and interactive user interface designs. Whether you're designing the flow of a multi-screen app, or new interactions and animations […]

Create atomic design ( http://bradfrost.com/blog/post/atomic-web-design/ ) systems with Pattern Lab.

… a specialized remote screen viewing application intended as a tool to help designers create graphics for mobile applications, it has also proven to be useful for creating quick and dirty simulations, demos, and experience prototypes.

… adapts your existing HTML images for mobile devices. No mark-up changes needed. Just drop it in and forget about it.

… makes it easy to quickly create high-quality custom controls for your iOS apps, Mac apps and for the web.