We are accepting both working and non-working prototypes (such as mock-ups), however if you have the skills on your team to create the app, this can improve your submission's ability to stand-out and become a portfolio piece.

If you're creating a working prototpye, you can use any tools you like - and are familiar with. You'll likely need a place to host the application, see below for some tips on how to do that if you don't have a preferred method.

If you're building any sort of web-connected application (be it web, mobile, or a desktop application) you'll need a server to host it on, and we reccomend utilizing the free tier of AWS. 

If your project, by virtue of its nature, doesn't already have a web presence (e.g. it's a mobile app or a game) then you're very likely going to need host a static website somewhere (i.e. A pile of HTML, CSS, and JavaScript) to give your project a home.

Probably the easiest and fastest way to achieve that at the moment is via GitHub Pages that hosts a website straight out of your GitHub repository. In addition to that, GitHub Pages provides the option to generate a project site from a collection of pre-built themes and to point your own custom domain at your site.

If you prefer to start from scratch (on GitHub Pages or elsewhere) Bootstrap and Foundation are the two preeminent responsive frontend web frameworks around these days that cut away a lot of the work of making a site look pretty so you can concentrate on content.