Design and develop a responsive web app template

I am looking for a designer/developer to create me a slick, minimal template for a new web app. It needs to be responsive so as to work on multiple devices, and have all the clever tricks built into it that allow adding to mobile homescreens, etc.

The design/site needs to do two jobs:

1. Explain what the app does and how it works (it's similar to Google Alerts, but it monitors a different kind of content)
2. Enable people to sign up quickly and easily (it just needs the keyword and an email address)

There is already a logo, and examples of the emails that subscribers receive can also be provided. Other than that, it's over to your imagination.

If you intend to bid for this project, please read the above carefully and ensure your response relates to what I have told you. Please provide examples of similar sites you have designed AND developed.

Many thanks.