It's EXTREMELY streamlined and simple to use, with a Ps-like interface for dealing with layers. I love it!

Nada, simplemente no me gusta nada de esta herramienta, el hecho de que estaba buscando una herramienta de prototipado rápido y que internet me aconsejara usar esta fue un error total.

What I like best about JustInMind is that you can choose to use it however you want, you can choose to create a Lo-Fi or a Hi-Fi prototype. It provides the tools to enhance a simple mock-up to display how you want the experience to be felt like before you begin writing a single line of code. Plus the free version offers many of the tools you need to have a basic prototype.